@article{meierThermalStabilitySkyrmions2026,

title = {Thermal stability of skyrmions},

author = {T. N. G. Meier and C. Back},

url = {http://dx.doi.org/10.1088/1361-648X/aeb085},

doi = {10.1088/1361-648x/aeb085},

issn = {1361-648X},

year  = {2026},

date = {2026-10-23},

urldate = {2026-10-01},

journal = {J. Phys.: Condens. Matter},

volume = {38},

number = {42},

pages = {423004},

publisher = {IOP Publishing},

abstract = {Magnetic skyrmions are vortex-like magnetic textures with a topologically nontrivial spin structure making a continuous transformation from the skyrmion to the uniform state impossible. Hence skyrmions are regarded as topologically protected attracting large interest concerning applications in data storage, neuromorphic computing, and digital logic. For such kind of applications an extraordinary stability of the skyrmion state against thermal fluctuations is required. In real matter, due to its discrete nature, topological protection translates into the existence of an energy barrier between the skyrmion and the uniform state leading to a finite skyrmion lifetime. Therefore the experimental determination of the skyrmion lifetime becomes important. Within this work we focus on experimental studies of the skyrmion lifetime in a variety of magnetic systems ranging from monolayers to bulk samples. We discuss previous experimental studies on the thermal stability of magnetic skyrmions in systems based on Fe/Ir(111) and in B20-materials. New experimental results on skyrmion nucleation and decay are obtained for thin Ni/Fe-films on Cu(001) using threshold photoemission magnetic circular dichroism in combination with photoemission electron microscopy (TP-MCD-PEEM). The results are interpreted using an Arrhenius-like activation behavior and evaluated regarding energy barriers and pre-exponential factors of the skyrmion dynamics.},

note = {datadoi: 10.14459/2026mp1859939},

keywords = {C2},

pubstate = {published},

tppubtype = {article}

}

@article{ranautFrustratedGarnetGd3Te2Li3O122026,

title = {Frustrated Garnet Gd_{3}Te_{2}Li_{3}O_{12} for High-Performance Sub-Kelvin Adiabatic Demagnetization Refrigeration},

author = {D. Ranaut and G. Unnikrishnan and Samraj M and S. K. Channarayappa and P. K. Mukharjee and P. Saravanan and P. Gegenwart and D. Jaiswal-Nagar},

url = {https://doi.org/10.1021/acsaelm.6c01619},

doi = {10.1021/acsaelm.6c01619},

issn = {2637-6113},

year  = {2026},

date = {2026-10-22},

urldate = {2026-10-01},

journal = {ACS Appl. Electron. Mater.},

abstract = {Owing to the limited availability and high cost of 3He, adiabatic demagnetization refrigeration (ADR) has gained considerable attention as an efficient technology for ultralow-temperature applications. Here, we demonstrate the frustrated garnet Gd3Te2Li3O12 (GTLG) as a high-performance ADR material with substantially improved cooling capability over the commercial benchmark Gd3Ga5O12 (GGG). Direct ADR measurements reveal a minimum temperature of 165 mK for GTLG, nearly two-fold lower than that of GGG (320 mK). Under a cryostat bath temperature of 1.8 K, GTLG maintains temperatures below 1 K for more than 12 h and below the 3He-temperature (0.4 K) for over 3 h, demonstrating excellent temperature stability for prolonged cryogenic operation. Magnetic and thermodynamic measurements show that GTLG undergoes antiferromagnetic ordering at TN ∼ 0.25 K while retaining strong magnetic frustration and a large magnetic entropy reservoir favorable for efficient demagnetization cooling. Field-dependent heat capacity and magnetic Grüneisen parameter measurements further reveal the presence of field-induced critical behavior that enables cooling below TN through enhanced entropy accumulation near the critical region. These findings establish GTLG as a promising next-generation magnetic refrigerant and highlight field-induced criticality as an effective design principle for developing advanced materials for ultralow-temperature refrigeration.},

keywords = {B1, B3},

pubstate = {published},

tppubtype = {article}

}

@article{prodan2026universalitymagneticsusceptibilityconical,

title = {Universality of magnetic susceptibility in the conical state of kagome ferromagnet Fe_{3}Sn_{2}},

author = {L. Prodan and D. M. Evans and L. Puntigam and I. Kézsmárki and V. Tsurkan},

url = {https://doi.org/10.1063/5.0342307},

doi = {10.1063/5.0342307},

year  = {2026},

date = {2026-10-13},

urldate = {2026-10-01},

journal = {Appl. Phys. Lett.},

volume = {129},

pages = {151905},

abstract = {We report universal behavior of the differential magnetic susceptibility (DMS) in the conical phase that mediates the spin-reorientation (SR) transition of the kagome ferromagnet Fe3Sn2. Within the SR temperature range, the DMS isotherms exhibit extremely narrow crossing regions, forming isosbestic points. Using an isosbestic-invariance analysis, we show that the isotherms collapse onto a single temperature-independent curve, revealing quadratic-in-temperature corrections to the susceptibility. Complementary field-dependent magnetic-force-microscopy measurements uncover the evolution of spin textures from stripe-like domains at low fields to isolated bubble-like domains near the isosbestic field (⁠ textasciitilde0.6T), a behavior not previously reported in bulk Fe3Sn2 within the conical state. These findings point to a universal mechanism for the emergence of complex magnetic textures near isosbestic points, driven by the competition between magnetocrystalline anisotropy, dipolar interactions, and external magnetic field.},

note = {datadoi: 10.5281/zenodo.15367272},

keywords = {A1, A4},

pubstate = {published},

tppubtype = {article}

}

@article{liuInformationTheoreticPrincipleEmergent2026,

title = {Information-Theoretic Principle of Emergent 1-Form Symmetries},

author = {Y. -J. Liu and W. -T. Xu and F. Pollmann and M. Knap},

url = {https://doi.org/10.1103/d6qf-5chk},

doi = {10.1103/d6qf-5chk},

issn = {2691-3399},

year  = {2026},

date = {2026-10-09},

urldate = {2026-10-01},

journal = {PRX Quantum},

volume = {7},

number = {4},

publisher = {American Physical Society (APS)},

note = {datadoi: 10.5281/zenodo.17652054},

keywords = {C5, C6},

pubstate = {published},

tppubtype = {article}

}

@article{schneiderLinearDichroicSoft2026,

title = {Linear dichroic soft x-ray microscopy of ferroelectric stripe domains in epitaxial K_{0.6}Na_{0.4}NbO_{3}},

author = {M. Schneider and T. A. Butcher and S. Wagner and D. Metternich and C. Klose and E. Malm and R. Battistelli and V. Deinhart and J. Fuchs and S. Wittrock and T. Karaman and K. Puzhekadavil Joy and M. Patra and F. Büttner and S. Wintz and M. Weigand and C. M. Günther and D. Engel and P. Gaal and J. Schwarzkopf and B. Pfau and S. Eisebitt},

url = {https://link.aps.org/doi/10.1103/kcjc-dtj6},

doi = {10.1103/kcjc-dtj6},

year  = {2026},

date = {2026-10-02},

urldate = {2026-10-01},

journal = {Phys. Rev. B},

volume = {114},

number = {23},

pages = {L231401},

publisher = {American Physical Society},

abstract = {Functional properties of ferroelectric thin films are governed by domains that can be engineered by epitaxial strain. Soft x-ray microscopy can image domain structures with elemental and electronic sensitivity, but hitherto its application to strain-stabilized domains has been hindered by the absorption of soft x-rays in epitaxial substrates. Here, it is demonstrated how this limitation can be overcome by locally back-thinning the (110) TbScO3 substrate of epitaxial K0.6⁢Na0.4⁢NbO3 ferroelectric thin films to achieve soft x-ray transparency at the O K-edge around 530 eV. Strain-induced ferroelectric stripe domains with periods down to 44 nm were resolved by scanning transmission x-ray microscopy and coherent diffractive imaging by exploiting the x-ray linear dichroism of hybridized O 2⁢𝑝–Nb 4⁢𝑑 states, providing sensitivity to in-plane polarization components under normal incidence. The results establish soft x-ray microscopy for nanoscale imaging of epitaxial ferroelectric domain structures and open perspectives for time-resolved studies thereof.},

note = {datadoi: 10.5281/zenodo.22250213.},

keywords = {C2},

pubstate = {published},

tppubtype = {article}

}

@article{mangeolleProbingTopologyThin2026,

title = {Probing topology in thin films with quantum Sondheimer oscillations},

author = {L. Mangeolle and J. Knolle},

url = {https://link.aps.org/doi/10.1103/l1gl-xdvv},

doi = {10.1103/l1gl-xdvv},

year  = {2026},

date = {2026-10-01},

journal = {Phys. Rev. B},

volume = {114},

number = {22},

pages = {225108},

publisher = {American Physical Society},

abstract = {Sondheimer oscillations (SO) are magnetoresistance oscillations occurring in thin films due to the commensurability between cyclotron motion and sample thickness, and are traditionally regarded as a purely semiclassical size effect. Here we develop a general quantum theory of SO for thin-film conductors in the quantum limit of a large magnetic field. We show that corrections arising from band topology modify the SO frequency, in contrast to Shubnikov–de Haas oscillations where topological information appears only in the phase. As a consequence, quantum SO provide a direct and robust probe of the full Landau level spectrum. Applying our framework to a minimal model with tunable Berry phase, we demonstrate how topology manifests itself in experimentally accessible magneto-oscillation spectra and discuss damping mechanisms including surface roughness.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{zhangSubstrateTuningStructural2026,

title = {Substrate tuning of the structural and electronic transition in thin flakes of the excitonic insulator candidate Ta_{2}NiSe_{5}},

author = {Y. -S. Zhang and Z. Yang and C. Xiao and M. Isobe and M. Minola and H. Takagi and D. Huang},

url = {https://doi.org/10.1038/s42005-026-02888-x},

doi = {10.1038/s42005-026-02888-x},

year  = {2026},

date = {2026-09-29},

urldate = {2026-09-01},

journal = {Commun. Phys.},

volume = {9},

pages = {309},

abstract = {Ta2NiSe5 continues to draw interest for its Tc = 326 K phase transition, whose dual electronic and structural nature reflects a complex interplay of electron-hole (excitonic) and electron-lattice interactions. The majority of studies that have attempted to decipher the relative importance of these interactions, particularly through charge tuning, have been focused on bulk samples. Here, we utilize an all-dry exfoliation and transfer protocol to isolate ultrathin flakes of Ta2NiSe5 on insulating Al2O3 and conducting Au. Using polarized Raman spectroscopy, we uncover the following substrate dependence: Four layers of Ta2NiSe5 on Al2O3 show a sharp structural and electronic transition that is lowered by roughly 40 K from the bulk Tc. Meanwhile, four layers of Ta2NiSe5 on Au undergo a structural and electronic transition that is much more gradual with respect to temperature and finishes roughly 150 K below the bulk Tc. The pronounced broadening points to an atomic-scale interface effect, wherein electrostatic screening and charge transfer from Au produces a Tc gradient perpendicular to the layers of the flake. We discuss the role of excitonic physics and suggest the possibility for interface engineering to pattern nanoscale junctions in Ta2NiSe5.},

note = {datadoi: 10.5281/zenodo.22107443},

keywords = {A3},

pubstate = {published},

tppubtype = {article}

}

@article{jawaleLowtemperatureMagnetismSpin2026,

title = {Low-temperature magnetism and spin dynamics in the disordered triangular-lattice Yb^{3+} compound LiCaYb_{5}(BO_{3})_{6}},

author = {M. Jawale and S. Nandi and P. K. Mukharjee and P. Gegenwart and A. V. Mahajan},

url = {https://link.aps.org/doi/10.1103/px8x-fcqp},

doi = {10.1103/px8x-fcqp},

year  = {2026},

date = {2026-09-25},

urldate = {2026-09-01},

journal = {Phys. Rev. B},

volume = {114},

number = {16},

pages = {165140},

publisher = {American Physical Society},

abstract = {The interplay between geometric frustration, spin-orbit coupling, and structural disorder can give rise to unconventional magnetic ground states in rare-earth triangular-lattice magnets. We report low-temperature magnetic and 7Li NMR investigations of the disordered triangular-lattice compound LiCaYb5(BO3)6 (LCYBO). Rietveld refinement confirms a hexagonal 𝑃⁢65⁢22 structure with partial Ca/Yb antisite disorder and fractional Li occupancy. Magnetic susceptibility and magnetization measurements indicate a well-isolated effective 𝐽eff=1/2 Kramers doublet with weak antiferromagnetic interactions (𝜃CW≈−0.54K). The specific heat reveals a weak anomaly near 0.43 K, suggesting the development of short-range correlated magnetism rather than conventional long-range order. 7Li NMR spectra broaden strongly upon cooling, consistent with increasingly inhomogeneous internal magnetic fields. The spin-lattice relaxation exhibits two relaxation components consistent with disorder-induced distributions of local magnetic environments arising from antisite disorder and competing exchange pathways. Our results establish LCYBO as a structurally disordered frustrated triangular-lattice magnet with correlated low-energy spin dynamics.},

keywords = {B3},

pubstate = {published},

tppubtype = {article}

}

@article{xn3r-b7g6,

title = {Magnetic symmetry and hyperfine fields of V_4 tetrahedral clusters in the multiferroic lacunar spinel GeV_{4}S_{8}},

author = {T. Gimpel and N. Büttgen and L. Prodan and V. Tsurkan and A. A. Tsirlin and H. Nakamura and I. Kézsmárki},

url = {https://link.aps.org/doi/10.1103/xn3r-b7g6},

doi = {10.1103/xn3r-b7g6},

year  = {2026},

date = {2026-09-18},

urldate = {2026-09-01},

journal = {Phys. Rev. B},

volume = {114},

number = {15},

pages = {154418},

abstract = {We use 51V nuclear magnetic resonance (NMR) spectroscopy to investigate the magnetic ground state of the lacunar spinel GeV4⁢S8, which undergoes a structural distortion at 𝑇JT≈30K followed by an antiferromagnetic (AFM) ordering at 𝑇𝑁≈15K. According to our zero- and finite-field NMR data, the four V-sites of V4 clusters become magnetically inequivalent in the AFM state: Two of them share the same internal field, while the other two sites are characterized by different internal fields. The angular dependence of the 51V NMR lines, upon rotation of an external magnetic field about the pseudocubic [110] and [100] axes, reveals that the internal fields are either parallel to the orthorhombic 𝑎 axis at all four V-sites of the V4 tetrahedra, or they form an orthogonal pattern, where two V-sites have internal field along the 𝑎 axis and the other two along the 𝑏 axis. Based on these results, further supported by the observation of distinct spin-echo modulations of the inequivalent V-sites, we conclude that the magnetic space group of the AFM state is 𝑃𝑏⁢𝑚⁢𝑛⁢21 or 𝑃⁢𝑚⁢𝑛′⁢2′1.},

note = {datadoi: (10.5281/zenodo.20604906)},

keywords = {B3, B4},

pubstate = {published},

tppubtype = {article}

}

@article{chatterjeeAnisotropicMagnetotransportOptical2026,

title = {Anisotropic magnetotransport and optical response of the multiband low-carrier antiferromagnet DyPtSb},

author = {S. Chatterjee and A. Agarwal and R. Borkenhagen and C. A. Kuntscher and M. J. Winiarski and O. Pavlosiuk and P. Wiśniewski and D. Kaczorowski},

url = {https://link.aps.org/doi/10.1103/lqnh-7d73},

doi = {10.1103/lqnh-7d73},

year  = {2026},

date = {2026-09-14},

urldate = {2026-09-01},

journal = {Phys. Rev. B},

volume = {114},

number = {15},

pages = {154412},

abstract = {We report a combined study of the magnetic, electrical transport, optical reflectivity, and electronic properties of single-crystalline DyPtSb, a half-Heusler antiferromagnet that orders at 2.2 K. The electrical resistivity exhibits semiconductor-like behavior and the Hall response becomes strongly nonlinear at low temperatures, indicating multiband transport with hole- and electron-type pockets. Angular magnetoresistance measurements revealed occurrence of twofold and fourfold symmetry components, both of which change sign near magnetic field of 4 T at 2 K, suggesting a field-induced modification of the electronic structure near the crossover from the antiferromagnetic to the spin-polarized regime. The optical spectroscopy revealed a temperature-dependent plasma edge and a Drude response, consistent with the bulk electrical transport data. In contrast to the characteristic feature of three-dimensional Dirac and Weyl semimetals, the optical conductivity of DyPtSb does not exhibit clear linear-in-frequency behavior at low energy. The results of ab initio electronic band-structure calculations revealed that the compound is a narrow-gap semiconductor, showing pronounced anisotropy of valence bands and strong sensitivity to magnetic polarization. DyPtSb was characterized as a multiband low-carrier antiferromagnet whose electrical transport properties are closely tied to the evolution of its electronic structure.},

keywords = {A1},

pubstate = {published},

tppubtype = {article}

}

@article{scopaGeneralizedHydrodynamicsBloch2026,

title = {Generalized Hydrodynamics of Bloch Oscillations in the Absence of a Lattice},

author = {S. Scopa and P. Zechmann and M. Knap and J. De Nardis and A. Bastianello},

url = {https://doi.org/10.1103/yfjc-r69d},

doi = {10.1103/yfjc-r69d},

issn = {1079-7114},

year  = {2026},

date = {2026-09-11},

urldate = {2026-09-01},

journal = {Phys. Rev. Lett.},

volume = {137},

number = {11},

publisher = {American Physical Society (APS)},

note = {datadoi: 10.5281/zenodo.20272044},

keywords = {C5, C6},

pubstate = {published},

tppubtype = {article}

}

@article{consoliTuningMagneticProperties2026,

title = {Tuning the Magnetic Properties of Kitaev Materials via the Antiferromagnetic Proximity Effect: Novel Phases and Application to an α-RuCl_{3}/MnPS_{3} Bilayer},

author = {P. M. Cônsoli and E. Day-Roberts and J. Knolle and A. S. Botana and O. Erten},

url = {https://doi.org/10.1021/acs.nanolett.6c03321},

doi = {10.1021/acs.nanolett.6c03321},

issn = {1530-6984},

year  = {2026},

date = {2026-09-08},

urldate = {2026-09-01},

journal = {Nano Lett.},

volume = {26},

number = {37},

pages = {12491–12499},

abstract = {In recent years, the increasing level of control over van der Waals (vdW) heterostructures has opened new routes to tune the properties of quantum materials. Motivated by these developments, we examine the potential consequences of interfacing a Kitaev honeycomb magnet, such as α-RuCl3, with a nearly lattice-matched vdW antiferromagnet. By combining perturbation theory, exact diagonalization, and a classical energy-minimization method, we show that an effective staggered magnetic field originating from the vdW antiferromagnet can drive a monolayer of a Kitaev material into various novel phases, including an antichiral Kitaev spin liquid, a nonmagnetic nematic phase, and different types of skyrmion crystals. We then apply first-principles simulations to assess the prospect of concretely realizing this setup in a heterobilayer of α-RuCl3 and the easy-axis antiferromagnet MnPS3.},

keywords = {B6},

pubstate = {published},

tppubtype = {article}

}

@article{8b8c-2wm3,

title = {Pressure-induced electronic delocalization and superconductivity in GaNb_{4}Se_{8}},

author = {Y. Wang and Z. Wu and K. C. Bhupendra and D. Zhang and L. Wang and S. V. Khare and L. Prodan and V. Tsurkan},

url = {https://link.aps.org/doi/10.1103/8b8c-2wm3},

doi = {10.1103/8b8c-2wm3},

year  = {2026},

date = {2026-09-04},

urldate = {2026-09-01},

journal = {Phys. Rev. B},

volume = {114},

number = {17},

pages = {175107},

publisher = {American Physical Society},

abstract = {Understanding how electronic transport evolves from localized to itinerant regimes in correlated cluster solids remains an important challenge in condensed-matter physics. Here, we investigate the pressure-dependent transport properties of the lacunar spinel GaNb4⁢Se8, a cluster Mott insulator at ambient conditions. At ambient pressure, the resistivity follows Efros-Shklovskii variable-range hopping, indicating Coulomb gap–controlled carrier localization. A pressure-induced electronic delocalization process begins at low pressures (∼5 GPa), as evidenced by the continuous suppression of room-temperature resistance. Upon further compression, the system undergoes a broad insulator-to-metal-like crossover in low-temperature transport, culminating in a fully metallic-like ground state at ∼17–18 GPa. In contrast, the crystallographic transition from the cubic phase to the monoclinic 𝐶⁢2 phase starts at ∼20 GPa and ends near ∼32 GPa, demonstrating that the pressure-induced electronic evolution is completed before the onset of long-range structural symmetry breaking. At higher pressures, superconductivity (with a superconducting coherence length ξ(0) ≈ 80–90 Å) emerges from a pressure-induced metallic-like regime. These results establish GaNb4⁢Se8 as a platform for studying correlation-driven evolution of electronic transport in cluster-based solids.},

keywords = {B4},

pubstate = {published},

tppubtype = {article}

}

@article{magnaterraRIXSObservationBonddirectional2026,

title = {RIXS observation of bond-directional excitations in the Kitaev material Na_{2}IrO_{3}},

author = {M. Magnaterra and K. Hopfer and C. J. Sahle and M. Moretti Sala and G. Monaco and J. Attig and C. Hickey and I. -M. Pietsch and F. Breitner and P. Gegenwart and M. H. Upton and J. Kim and S. Trebst and P. H. M. Loosdrecht and J. Brink and M. Grüninger},

url = {https://doi.org/10.1038/s41535-026-00938-9},

doi = {10.1038/s41535-026-00938-9},

year  = {2026},

date = {2026-09-03},

urldate = {2026-09-01},

journal = {npj Quantum Mater.},

volume = {11},

pages = {85},

abstract = {Spin-orbit coupling locks spin direction and spatial orientation and generates, in semi-classical magnets, a local spin easy-axis and associated ordering. Quantum spin-1/2’s defy this fate: rather than spins becoming locally anisotropic, the spin-spin interactions do. Consequently interactions become dependent on the spatial orientation of bonds between spins, prime theoretical examples of which are Kitaev magnets. Bond-directional interactions imply the existence of bond-directional magnetic modes, spin excitations that render crystallographically equivalent bonds magnetically inequivalent, which yet have remained elusive experimentally. Here we show that resonant inelastic X-ray scattering allows us to explicitly probe the bond-directional character of magnetic excitations. To do so, we use a scattering plane spanned by one bond and the corresponding spin component and scan a range of momentum transfer that encompasses multiple Brillouin zones. Applying this approach to Na2IrO3 we establish the different bond-directional characters of magnetic excitations at textasciitilde10 meV and textasciitilde45 meV. The bond-directional nearest-neighbor excitations are a fingerprint of the dominant Kitaev interactions and even prevail in the magnetically ordered state.},

keywords = {B1},

pubstate = {published},

tppubtype = {article}

}

@article{l5xq-2yrt,

title = {Electronic tuning of the soft-phonon transport anomaly in Ta_{2}Ni(S_{x}Se_{1-x})_{5}},

author = {Y. -S. Zhang and M. Isobe and H. Takagi and D. Huang},

url = {https://link.aps.org/doi/10.1103/l5xq-2yrt

https://doi.org/10.5281/zenodo.21493304},

doi = {10.1103/l5xq-2yrt},

year  = {2026},

date = {2026-09-02},

urldate = {2026-09-02},

journal = {Phys. Rev. Lett.},

volume = {137},

number = {10},

pages = {106503},

abstract = {Ta2⁢NiSe5 continues to be investigated for its phase transition at 𝑇c=326 K, where it develops both an electronic gap and a distortion of its Ta/Ni chains. One intriguing feature at 𝑇c seen in thermal transport is the giant anisotropic scattering of phonons moving perpendicular to the chains, which is apparently associated with the softening of a transverse acoustic phonon, but whose microscopic origin and significance demand clarification. By tuning the normal-state band overlap or gap with S substitution, we uncover a close connection between this soft-phonon transport anomaly and underlying electronic instabilities: when Ta2⁢Ni⁢(S𝑥⁢Se1−𝑥)5 approaches a band insulator at high 𝑥, and signatures of the electronic transition are suppressed, the soft-phonon transport anomaly concomitantly vanishes. Our results establish the following picture for the Ta2⁢Ni⁢(S𝑥⁢Se1−𝑥)5 family: near the S end, a sole lattice instability gives rise to a weak structural transition with 𝑇c approaching 130 K. Near the Se end, additional electronic instabilities boost 𝑇c up to 326 K and amplify experimental signatures of the transition. The strong interaction between electrons, holes, and the lattice is manifested as a soft-phonon transport anomaly accompanied by electronic fluctuations, which include excitonic and hybridization-gap fluctuations.},

note = {datadoi: 10.5281/zenodo.21493304},

keywords = {A3},

pubstate = {published},

tppubtype = {article}

}

@article{laoAlloyingcontrolledTuningInterfacial2026,

title = {Alloying‐controlled tuning of interfacial spin‐orbit interaction and magnetic damping in crystalline FeCo thin films grown on GaAs(001)},

author = {H. Lao and M. Kronseder and Z. Yuan and T. Narr and T. N. G. Meier and N. Mundigl and X. Qu and Z. Wang and C. H. Back and L. Chen},

url = {http://dx.doi.org/10.1002/adma.74841},

doi = {10.1002/adma.74841},

issn = {1521-4095},

year  = {2026},

date = {2026-08-28},

urldate = {2026-08-01},

journal = {Adv. Mater.},

publisher = {Wiley},

abstract = {The discovery of intrinsic spin–orbit fields in non-centrosymmetric ferromagnets have attracted considerable interest for both fundamental studies and technological applications. However, once such materials are synthesized, the strength of the spin-orbit fields is difficult to tune because it is primarily a bulk property. Here, we demonstrate that the interfacial spin-orbit interaction (SOI) in single-crystalline Fe1−xCox thin films grown on GaAs(001) can be continuously tuned via alloying. Using spin-orbit ferromagnetic resonance, we find that the Landé g-factor, the Gilbert damping α, and the interfacial spin-orbit fields exhibit a common nonmonotonic dependence on Co concentration. A pronounced minimum occurs near x ≈ 0.2 where an ultra-low damping α ≈ 0.0015 is achieved. Furthermore, we observe linear scaling between α and (g − 2)2, suggesting that interfacial SOI may also contribute to magnetic relaxation. These results identify alloying as an effective knob to engineer interfacial SOI and damping in single crystalline ferromagnet/semiconductor heterostructures.},

keywords = {A2},

pubstate = {published},

tppubtype = {article}

}

@article{salgado-linaresThermalHallConductivity2026,

title = {Thermal Hall conductivity from semiclassical spin dynamics simulations: Implementation and applications to chiral ferromagnets and Kitaev magnets},

author = {I. Salgado-Linares and A. Mook and L. Mangeolle and J. Knolle},

url = {https://link.aps.org/doi/10.1103/b1r9-1l3f},

doi = {10.1103/b1r9-1l3f},

year  = {2026},

date = {2026-08-21},

urldate = {2026-08-21},

journal = {Phys. Rev. B},

volume = {114},

number = {12},

pages = {125123},

publisher = {American Physical Society},

abstract = {We investigate thermal Hall transport in magnetic systems, using semiclassical spin dynamics simulations. Building on a linear response framework, we discuss the intricacies of computing the thermal Hall conductivity from real-time energy current correlations and the energy magnetization. We then apply this methodology to two models: a square-lattice chiral magnet with in-plane Dzyaloshinskii-Moriya interaction, and the antiferromagnetic Kitaev model in a field. Our results demonstrate the efficiency of semiclassical spin dynamics to study thermal Hall transport capturing quantitative effects beyond the simple intrinsic noninteracting approximation. They can serve as a benchmark for comparison with experiments in regimes where nonlinearities from magnon-magnon interactions and strong thermal fluctuations play a crucial role.},

keywords = {C6},

pubstate = {published},

tppubtype = {article}

}

@article{sunObservationConformalField2026,

title = {Observation of conformal field theory spectra in a quantum simulator},

author = {X. Sun and Y. Le and S. Naus and R. B. -S. Tsai and L. R. B. Picard and S. Murciano and M. Knap and J. Alicea and M. Endres},

url = {https://doi.org/10.1038/s41586-026-10904-x},

doi = {10.1038/s41586-026-10904-x},

issn = {1476-4687},

year  = {2026},

date = {2026-08-19},

urldate = {2026-08-01},

journal = {Nature},

volume = {657},

number = {8130},

pages = {98–106},

publisher = {Springer Science and Business Media LLC},

keywords = {C5, C6},

pubstate = {published},

tppubtype = {article}

}

@article{fazlizhanovEvolutionLowtemperatureElectron2026,

title = {Evolution of low-temperature electron spin resonance in Y(Rh_{0.73}Co_{0.27})_{2}Si_{2} upon entering ferromagnetic order},

author = {I. Fazlizhanov and Z. Y. Seidov and H. -A. Krug von Nidda and C. Krellner and C. Klingner and L. Pedrero and S. Lausberg and M. Brando and C. Geibel and F. Steglich and J. Sichelschmidt},

url = {https://link.aps.org/doi/10.1103/csyd-6npb},

doi = {10.1103/csyd-6npb},

year  = {2026},

date = {2026-08-17},

urldate = {2026-08-01},

journal = {Phys. Rev. B},

volume = {114},

number = {11},

pages = {115117},

publisher = {American Physical Society},

abstract = {We report electron spin resonance (ESR) experiments conducted on oriented powder of the heavy-fermion ferromagnet Yb⁢(Rh0.73⁢Co0.27)2⁢Si2 in the temperature range 0.75≤𝑇≤4K, which includes the transition between the paramagnetic and ferromagnetic ordered phases below the Curie temperature 𝑇C=1.3K. The ESR measurements were performed using a home-built 3He cryostat at 𝑋-band frequencies. In the ferromagnetic ordered phase the ESR spectra of Yb⁢(Rh0.73⁢Co0.27)2⁢Si2 are split into two lines. While the resonance in the paramagnetic phase features an easy-plane crystalline electric field induced anisotropy of the 𝑔 tensor perpendicular to the 𝑐 axis of the tetragonal crystal structure, the split lines in the ordered phase can be related to ferromagnetic resonance modes with a uniaxial exchange-type anisotropy along the 𝑐 axis. The corresponding effective anisotropy field can be determined.},

keywords = {B4},

pubstate = {published},

tppubtype = {article}

}

@article{yueElectromagneticResponseHalfFilled2026,

title = {Electromagnetic Response of a Half-Filled Chern Band near Topological Criticality},

author = {X. Yue and F. Pichler and M. Knap and A. Stern},

url = {https://doi.org/10.1103/v44d-7jr4},

doi = {10.1103/v44d-7jr4},

issn = {1079-7114},

year  = {2026},

date = {2026-08-14},

urldate = {2026-08-01},

journal = {Phys. Rev. Lett.},

volume = {137},

number = {7},

publisher = {American Physical Society (APS)},

keywords = {C5, C6},

pubstate = {published},

tppubtype = {article}

}

@article{xcr2-rxv6,

title = {Dynamic spin fluctuations in the S = ⁵⁄₂ tetratrillium lattice antiferromagnet KBaFe_{2}(PO_{4})_{3}},

author = {S. J. Sebastian and S. S. Islam and R. Kolay and S. Mohanty and Q. -P. Ding and Y. Skourski and J. Sichelschmidt and M. Baenitz and J. A. Krieger and T. J. Hicken and H. Luetkens and A. A. Tsirlin and Y. Furukawa and R. Nath},

url = {https://link.aps.org/doi/10.1103/xcr2-rxv6},

doi = {10.1103/xcr2-rxv6},

year  = {2026},

date = {2026-08-11},

urldate = {2026-08-01},

journal = {Phys. Rev. B},

volume = {114},

number = {8},

pages = {L080403},

abstract = {The three-dimensional (3D) magnet KBaFe2(PO4)3 hosts an effective tetratrillium spin lattice of Fe3+ (𝑆=5/2) ions, offering a prototypical platform to study frustration-driven phenomena in 3D. Through magnetization, specific heat, 31P nuclear magnetic resonance (NMR), and muon spin relaxation (µ⁢SR) experiments, supported by first-principles calculations, we uncover an unconventional ground state. Despite strong antiferromagnetic interactions with a large Curie-Weiss temperature 𝜃CW=−70⁢(2)⁢K, no magnetic long-range order is observed down to 30 mK. Below 𝑇*≃3.5K, the NMR linewidth becomes nearly field independent and the spin-spin relaxation rate 1/𝑇2 saturates, accompanied by a two-component relaxation in the transverse nuclear magnetization 𝑀𝑥⁢𝑦. The latter indicates the emergence of short-range dynamical correlations, which was further corroborated by a robust and field-insensitive broad maximum in specific heat. In µ⁢SR, we detect neither a static internal field nor spin freezing; instead, the spins remain dynamic down to 30 mK and the asymmetry curves are best described by two coexisting dynamic relaxation channels: a dominant fast (sporadic) channel and a slower Markovian component. Their differing weights and fluctuation rates suggest microscopic inhomogeneity in spin dynamics. These persistent low-temperature spin fluctuations are found to be intrinsic to the 3D frustrated tetratrillium geometry, exemplifying KBaFe2(PO4)3, a rare 3D antiferromagnet with a classical spin that fosters unconventional dynamics.},

keywords = {B3},

pubstate = {published},

tppubtype = {article}

}

@article{belbaseFiniteSpinonDensity2026,

title = {Finite spinon density of states in triangular lattice delafossite TlYbSe_{2}},

author = {B. P. Belbase and A. Unnikrishnan and S. Feng and E. S. Choi and J. Knolle and A. Banerjee},

url = {https://link.aps.org/doi/10.1103/tc4h-cq9c},

doi = {10.1103/tc4h-cq9c},

year  = {2026},

date = {2026-08-11},

urldate = {2026-08-01},

journal = {Phys. Rev. Res.},

volume = {8},

number = {3},

pages = {L032021},

publisher = {American Physical Society},

abstract = {We introduce the rare-earth delafossite compound TlYbSe2 — extending the search for quantum spin liquids in frustrated triangular lattice magnets. While the dc magnetization suggests magnetic exchange interactions on the order of several kelvin, the zero-field ac magnetization and heat capacity measurements reveal no signs of long-range magnetic order down to 20 mK, indicating a quantum-disordered ground state. We observe a spin-freezing transition near ∼30mK at zero field that is suppressed by an applied magnetic field of ∼0.02T. A broad anomaly in the heat capacity measurements between 2 and 5 K is indicative of short-range spin correlations. Below 350 mK, we observe a robust linear temperature dependence of the heat capacity, accompanied by the complete absence of long-range order at low fields. We propose that a phenomenological theory, based on the interplay between spinons and thermally excited gauge flux excitations, can account for the linear temperature dependence of the heat capacity, and could be widely applicable to similar critical quantum spin liquid candidate materials. The results establish the low-temperature, low-field regime of TlYbSe2 as a prime candidate for field-tunable triangular quantum spin liquid behavior and highlight the importance of thermally excited gauge field excitations.},

note = {datadoi: 10.5281/zenodo.21481296},

keywords = {B6},

pubstate = {published},

tppubtype = {article}

}

@article{leebCollinearpWaveMagnetism2026,

title = {Collinear p-Wave Magnetism and Hidden Orbital Ferrimagnetism},

author = {V. Leeb and J. Knolle},

url = {https://link.aps.org/doi/10.1103/ydjj-6r9l},

doi = {10.1103/ydjj-6r9l},

year  = {2026},

date = {2026-08-01},

journal = {Phys. Rev. Lett.},

volume = {137},

number = {10},

pages = {106701},

publisher = {American Physical Society},

abstract = {In the absence of spin-orbit coupling, collinear magnets are classified as even-wave magnets, i.e., either ferromagnets, antiferromagnets, or altermagnets. It is based on the belief that collinear magnets always feature an inversion-symmetric band structure, which forbids odd-parity magnetism. Here, we show that collinear magnets, which break time-reversal symmetry in the nonmagnetic sector, e.g., through loop currents, can have an inversion-symmetry-broken band structure and lead to unconventional types of collinear magnets. Hence, collinear odd-parity magnets do exist, and we explain that a magnetic field-induced Edelstein effect is their unique signature. We propose minimal models based on the coexistence of antiferromagnet order with compensated loop current orders for all types of collinear magnets. Our Letter provides a new perspective on collinear magnets and the spin-space group classification.},

note = {datadoi: 10.5281/zenodo.18456373},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{GIPPIUS2026174177,

title = {Short-range helical magnetic order in FeP_{1-x}As_{x} (x = 0.33 and 0.5)},

author = {A. A. Gippius and S. V. Zhurenko and A. V. Tkachev and A. V. Gunbin and N. Büttgen and M. Schaedler and I. G. Silkin and I. V. Morozov and A. V. Bogach and A. V. Sobolev and I. A. Presniakov and A. S. Moskvin},

url = {https://www.sciencedirect.com/science/article/pii/S0304885326003689},

doi = {10.1016/j.jmmm.2026.174177},

year  = {2026},

date = {2026-08-01},

urldate = {2026-08-01},

journal = {J. Magn. Magn. Mater.},

volume = {651},

pages = {174177},

abstract = {Although the FeP1-xAsx solid solution compounds are isostructural with the binary helimagnets FeP and FeAs with MnP-type structure (sp. gr. Pnma) of the B31 family, their magnetic structure remained unclear. We studied two members of this family (x = 0.33 and 0.5) via microscopic site-selective techniques such as Mössbauer and NMR spectroscopy. Our results indicate that the helimagnetic nature of the ground state is preserved, but undergoes significant modifications. In particular, its ordering range seems to become drastically shorter, so that the local fields on the non-magnetic phosphorus atoms decrease several times compared to those in FeP, and even local fields on iron slightly decrease compared to FeP and FeAs. The ordering temperature for these fragmented structures is suppressed down to 20–30 K, which is significantly lower than the TN values for FeP and FeAs. Additionally, both compounds demonstrate higher sustainability to the external field than the parent compound FeP.},

keywords = {B4},

pubstate = {published},

tppubtype = {article}

}

@article{chmerukSuppressionMagnetismCo3Sn2S22025,

title = {Suppression of magnetism in Co_{3}Sn_{2}S_{2} under external pressure},

author = {A. Chmeruk and D. Jones and R. Dwadasi and J. Ebad-Allah and F. Beiuşeanu and F. Schilberth and M. A. Kassem and U. Schade and A. Veber and L. Puskar and Y. Tabata and T. Waki and H. Nakamura and C. A. Kuntscher and A. Östlin and L. Chioncel},

url = {https://link.aps.org/doi/10.1103/v623-m3y4},

doi = {10.1103/v623-m3y4},

year  = {2026},

date = {2026-07-28},

urldate = {2026-07-28},

journal = {Phys. Rev. B},

volume = {114},

number = {2},

pages = {024423},

abstract = {The ability to control the magnetic state provides a powerful means to tune the underlying band topology, enabling transitions between distinct electronic phases and the emergence of novel quantum phenomena. In this work, we address the evolution of the ferromagnetic state in Co3⁢Sn2⁢S2 upon applying external pressures up to 10.8 GPa using a combined experimental and theoretical study. The standard ab initio density functional theory computation, including ionic relaxations grossly overestimates the unit cell magnetization as a function of pressure. In our theoretical analysis we identify two possible mechanisms to remedy this shortcoming. Matching the experimental observations is achieved by a symmetry-preserving adjustment of the sulfur atom positions within the unit cell. Alternatively, we explore various combinations of the exchange and correlation parts of the effective potential that reproduce the experimental magnetization, the structural parameters and the measured optical conductivity spectra. Thus, the pressure-dependent behavior of the magnetization demands a careful theoretical treatment and analysis of both theoretical and experimental data.},

keywords = {A1, A5},

pubstate = {published},

tppubtype = {article}

}

@article{lanziniTheoryAngleResolved2026,

title = {Theory of Angle Resolved Photoemission Spectroscopy of Altermagnetic Mott Insulators},

author = {L. Lanzini and P. Das and M. Knap},

url = {https://doi.org/10.1103/1d1n-cssv},

doi = {10.1103/1d1n-cssv},

issn = {1079-7114},

year  = {2026},

date = {2026-07-28},

urldate = {2026-07-01},

journal = {Phys. Rev. Lett.},

volume = {137},

number = {5},

publisher = {American Physical Society (APS)},

note = {datadoi: 10.5281/zenodo.15553362},

keywords = {C5, C6},

pubstate = {published},

tppubtype = {article}

}

@article{hollricherCyclotronMassselectiveHaas2026,

title = {Cyclotron mass-selective de Haas–van Alphen measurements using temperature modulation},

author = {M. Hollricher and A. Bauer and L. Maximov and L. Feenstra and C. Pfleiderer and M. A. Wilde},

url = {https://doi.org/10.1063/5.0334928},

doi = {10.1063/5.0334928},

issn = {0003-6951},

year  = {2026},

date = {2026-07-27},

urldate = {2026-07-27},

journal = {Appl. Phys. Lett.},

volume = {129},

number = {4},

pages = {041902},

abstract = {We present a temperature-modulated de Haas–van Alphen measurement technique that allows selective addressing of quantum oscillations with different effective masses m∗ using a non-monotonic amplitude evolution with temperature and magnetic field, governed by the temperature derivative of the Lifshitz–Kosevich factor. The technique relies on harmonic modulation of the sample temperature and phase-sensitive detection of quantum oscillations in the voltage induced in a pickup coil. We use a set of frequencies with strong Zeeman-driven harmonic content in the compensated topological semimetal MoSi2 as a natural linear mass comb ranging from 1 m∗ to 13 m∗ to demonstrate the tunability of the mass-dependent quantum oscillation amplitudes experimentally. The technique allows us to reliably isolate weak contributions of heavy orbits that are inaccessible in conventional de Haas–van Alphen frequency spectra because their frequency peaks overlap with much stronger frequency peaks of lighter orbits.},

keywords = {A6, C1},

pubstate = {published},

tppubtype = {article}

}

@article{fengTransientLocalizationFractionalization2026,

title = {Transient localization from fractionalization: Vanishingly small energy transport in gapless quantum magnets},

author = {S. Feng and P. Zhu and J. Knolle and M. Knap},

url = {https://doi.org/10.1103/crq3-l1r3},

doi = {10.1103/crq3-l1r3},

year  = {2026},

date = {2026-07-21},

urldate = {2026-07-21},

journal = {Phys. Rev. B},

volume = {114},

number = {3},

pages = {034423},

abstract = {In this work, we investigate zero-temperature energy transport in a gapless quantum magnet. We find that suppressed energy transport can arise at low frequencies due to transient localization from fractionalization, even in the absence of extrinsic defects or disorder. Concretely, we consider a Kitaev ladder model, whose spin degrees of freedom fractionalize into visons and spinons, in a uniform magnetic field. For moderate magnetic fields, visons are heavy and act as quasistatic disorder that induces transient localization of light spinons even in the translation-invariant model and at zero temperature, which strongly suppresses the residual transport.},

note = {datadoi: 10.5281/zenodo.17151126},

keywords = {B6, C5, C6},

pubstate = {published},

tppubtype = {article}

}

@article{gharaHighfieldCrossoverLinear2026,

title = {High-field crossover from linear to nonlinear magnetoelectric effect in Co_{3}O_{4}},

author = {S. Ghara and Y. Kinoshita and A. Miyake and Y. Ishii and L. Prodan and V. Tsurkan and Y. Skourski and J. Wosnitza and Y. H. Matsuda and S. Miyahara and M. Tokunaga and I. Kézsmárki},

url = {https://link.aps.org/doi/10.1103/j66k-pc7d},

doi = {10.1103/j66k-pc7d},

issn = {2469-9950, 2469-9969},

year  = {2026},

date = {2026-07-20},

urldate = {2026-07-20},

journal = {Phys. Rev. B},

volume = {114},

number = {2},

pages = {024417},

abstract = {The 𝐴-site magnetic spinel Co3⁢O4 exhibits a simple Néel-type collinear antiferromagnetic ordering below 𝑇𝑁=30 K, accompanied by a strong linear magnetoelectric effect. Here, we report magnetization and electric polarization measurements on single crystals of Co3⁢O4 up to high magnetic fields. We show that the magnetoelectric polarization undergoes a crossover from linear to nonlinear behavior with increasing magnetic field, followed by complete suppression upon reaching the field-polarized ferromagnetic state, where inversion symmetry is recovered. Our microscopic spin model, reproducing the observed field evolution of the magnetoelectric response, evidences weak anisotropy that is crucial for the effective magnetoelectric control of the antiferromagnetic state [Phys. Rev. Lett. 135, 126704 (2025)].},

note = {datadoi: 10.5281/zenodo.21078310},

keywords = {A4},

pubstate = {published},

tppubtype = {article}

}

@article{opletalComplexMagneticBehavior2026,

title = {Complex magnetic behavior of the Ce sawtooth chains in CeRhSn_{2}},

author = {P. Opletal and J. Fikáček and E. Duverger–Nédellec and A. Thamizhavel and Z. Hossain and R. Tarasenko and V. Tkáč and D. Legut and Bin Shen and P. Gegenwart and J. Custers},

url = {https://link.aps.org/doi/10.1103/pkdg-n4yk},

doi = {10.1103/pkdg-n4yk},

year  = {2026},

date = {2026-07-17},

urldate = {2026-07-01},

journal = {Phys. Rev. B},

volume = {114},

number = {4},

pages = {045118},

publisher = {American Physical Society},

abstract = {Conflicting reports exist on the ground state of the intermetallic compound CeRhSn2. This can be rooted in the sawtoothlike arrangement of two inequivalent Ce sites in the unit cell, which suggests potential geometric magnetic frustration. To resolve these conflicting reports, we conducted a comprehensive study on high-quality single crystals of CeRhSn2 by means of magnetization (𝑀), specific heat (𝐶p/𝑇), and resistivity (𝜌). The system exhibits strong magnetic anisotropy, confirming the 𝑏 axis as the easy magnetic axis. We establish three successive transitions: an antiferromagnetic order at 𝑇N=3.65K, a first-order ferromagnetic (FM) order at 𝑇C=1.7K and final transition, at 𝑇=1.5K. The transition temperatures are highly field-directional dependent: in a magnetic field, the lowest transition is immediately suppressed while 𝐇∥𝑏 rapidly merges 𝑇C and 𝑇N into a single second-order transition. Conversely, 𝐇∥𝑐 suppresses the FM order and reduces 𝑇N. Additional ab initio calculations affirm the FM ground state of CeRhSn2. The observation of an enhancement of the Sommerfeld coefficient (𝛾=76.5mJ/molK2) may arise from geometric frustration, but it is most consistently attributed to weak Kondo hybridization as frustration cannot be conclusively established through our data.},

note = {datadoi: 10.5281/zenodo.20434110},

keywords = {B3},

pubstate = {published},

tppubtype = {article}

}

@article{boeslSkeletonIsometricTensor2026,

title = {Skeleton of Isometric Tensor Network States for Abelian String-Net Models},

author = {J. Boesl and Y. -J. Liu and F. Pollmann and M. Knap},

url = {https://doi.org/10.1103/d3fz-5755},

doi = {10.1103/d3fz-5755},

issn = {1079-7114},

year  = {2026},

date = {2026-07-07},

urldate = {2026-07-01},

journal = {Phys. Rev. Lett.},

volume = {137},

number = {2},

publisher = {American Physical Society (APS)},

note = {datadoi: 10.5281/zenodo.17427675},

keywords = {C5, C6},

pubstate = {published},

tppubtype = {article}

}

@article{lamp:ChargeDynamics2026,

title = {Charge dynamics in the Weyl semimetals NbIrTe_{4} and TaIrTe_{4} under pressure: Signatures of an electronic phase transition},

author = {M. Lamp and J. Ebad-Allah and A. Chmeruk and N. Bura and R. Schönemann and L. Balicas and S. H. Lee and Z. Q. Mao and L. Chioncel and C. A. Kuntscher},

url = {https://link.aps.org/doi/10.1103/pvhn-prsw},

doi = {10.1103/pvhn-prsw},

year  = {2026},

date = {2026-07-06},

urldate = {2026-07-01},

journal = {Phys. Rev. B},

volume = {114},

number = {6},

pages = {065101},

abstract = {A high-pressure investigation of the Weyl semimetals NbIrTe4 and TaIrTe4 is presented, using infrared spectroscopy supplemented by density functional theory calculations. The experimental optical conductivity spectra as a function of pressure suggest the occurrence of a pressure-induced phase transition at a critical pressure P_c = 7-8 GPa. This transition is most likely electronic in nature, as Raman scattering measurements provide no evidence of a significant structural phase transition. Above P_c a significant redistribution of spectral weight occurs in the optical conductivity spectrum for both materials. A Drude-Lorentz analysis of the optical data indicates a sharp reduction in the free carrier concentration at P_c, concomitant with the appearance of a low-energy phonon, which was initially screened by free charge carriers. A predominantly electronic origin of the phase transition is supported by the calculated electronic band structure, Fermi surface, and interband optical conductivity as a function of pressure. Our findings provide collective evidence for a pressure-induced, most likely electronic phase transition in both van der Waals materials at P_c=7-8 GPa, highlighting the tunability of their electronic band structure by hydrostatic pressure.},

note = {datadoi: 10.5281/zenodo.20604906},

keywords = {A1, A5},

pubstate = {published},

tppubtype = {article}

}

@article{ojeda-aristizabalLessonsARuCl_3Pursuing2026,

title = {Lessons from α-RuCl_{3} for pursuing quantum spin liquid physics in atomically thin materials},

author = {C. Ojeda-Aristizabal and X. Zheng and C. Xu and Z. Nussinov and Y. Motome and A. Banerjee and A. W. Tsen and M. Knap and R. -R. Du and G. Joshi and A. Mounce and Y. Kim and B. M Hunt and D. Shcherbakov and B. Zhou and R. Jing and M. Liu and H. Zhao and M. Claassen and O. Erten and Y. P. Chen and E. A. Henriksen},

url = {https://iopscience.iop.org/article/10.1088/1361-648X/ae7cc8},

doi = {10.1088/1361-648x/ae7cc8},

issn = {1361-648X},

year  = {2026},

date = {2026-07-03},

urldate = {2026-07-01},

journal = {J. Phys. Condens. Matter},

volume = {38},

number = {26},

pages = {263001},

publisher = {IOP Publishing},

keywords = {C5, C6},

pubstate = {published},

tppubtype = {article}

}

@article{breitner2026magneticelectricpropertiesmetallic,

title = {Magnetic and electric properties of the metallic kagome antiferromagnet CrRhAs},

author = {F. Breitner and B. Shen and A. Jesche and A. A. Tsirlin and P. Gegenwart},

url = {https://link.aps.org/doi/10.1103/d449-1tfw},

doi = {10.1103/d449-1tfw},

year  = {2026},

date = {2026-06-30},

urldate = {2026-06-01},

journal = {Phys. Rev. Mater.},

volume = {10},

number = {6},

pages = {064204},

abstract = {CrRhAs is an antiferromagnetic kagome metal predicted to host a nontrivial spin texture with vector spin chirality [Huang et al., npj Quantum Mater. 8, 32 (2023)]. We report the synthesis and basic characterization of CrRhAs single crystals, which exhibit an antiferromagnetic transition with 𝑇N = 150 K, evidenced by electrical transport, heat capacity, and magnetization measurements. Hall resistivity varies linearly with magnetic field, i.e., there is no nonlinear Hall contribution. Intriguingly, the Hall coefficient changes sign between the configurations of 𝑗∥𝑎⁢𝑏, 𝐻⁡⊥⁢𝑎⁢𝑏 and 𝑗∥𝑐, 𝐻⁡⊥⁢𝑐, which is likely connected to a peculiar topology of the Fermi surface. Furthermore, for 𝑗∥𝑎⁢𝑏, the Hall coefficient shows a pronounced and continuous enhancement below 𝑇N, signaling a significant reconstruction of the Fermi surface or an extra scattering from the magnons. Our results offer guidance for exploring anomalous electrical transport phenomena in exotic magnetic systems.},

note = {datadoi: 10.5281/zenodo.19046826},

keywords = {B3},

pubstate = {published},

tppubtype = {article}

}

@article{baderTriangular$J_1textensuremathJ_2$Heisenberg2026,

title = {Triangular J_{1}-J_{2} Heisenberg antiferromagnet in a magnetic field},

author = {T. Bader and S. Feng and S. Budaraju and F. Becca and J. Knolle and F. Pollmann},

url = {https://link.aps.org/doi/10.1103/rwhz-jf5b},

doi = {10.1103/rwhz-jf5b},

year  = {2026},

date = {2026-06-18},

urldate = {2026-06-01},

journal = {Phys. Rev. B},

volume = {113},

number = {24},

pages = {L241114},

publisher = {American Physical Society},

abstract = {The behavior of the paradigmatic 𝐽1−𝐽2 triangular lattice Heisenberg antiferromagnet in a magnetic field remains unsettled despite decades of study. We map out the phase diagram using three complementary approaches, including self-consistent nonlinear spin-wave theory, density-matrix renormalization group, and variational Monte Carlo. This combined analysis resolves the competition among different field-induced magnetic orders and magnetization plateaus across the classically frustrated parameter range. In particular, there is a finite range in the parameter regime around 𝐽2/𝐽1 = 1/8 in which (i) upon the application of the external field, the gapless quantum spin liquid acquires a finite density of monopoles, and (ii) by further increasing the field, two plateaus are clearly obtained at 𝑚=1/3 and 𝑚=1/2. We discuss the experimental importance of the consecutive magnetization plateau transitions as a signature of an underlying quantum spin-liquid phase.},

note = {datadoi: 10.5281/zenodo.20510149},

keywords = {B6},

pubstate = {published},

tppubtype = {article}

}

@article{dp4g-dyll,

title = {Observation of surface ferromagnons in the axion-insulating phase of the antiferromagnetic topological insulator EuSn_{2}As_{2}},

author = {M. Hemmida and S. Pakhira and D. C. Johnston and H. -A. Krug von Nidda},

url = {https://link.aps.org/doi/10.1103/dp4g-dyll},

doi = {10.1103/dp4g-dyll},

year  = {2026},

date = {2026-06-17},

urldate = {2026-06-01},

journal = {Phys. Rev. Research},

volume = {8},

number = {2},

pages = {023309},

abstract = {We report the study of spin dynamics of Eu2+ in the antiferromagnetic axion topological insulator EuSn2⁢As2 by means of antiferromagnetic resonance at 9.34 GHz. Below the Néel temperature (T_N), two types of resonance modes, the conventional bulk antiferromagnetic resonance and additional surface ferromagnetic resonance, are observed. The latter turns out to be characteristic of the axion-insulating phase. Above T_N, we prove the existence of a Kosterlitz-Thouless scenario that is relevant for the spin relaxation in the Eu2+ layers. The absence of Korringa relaxation indicates the strong confinement of the conduction electrons at the Fermi level to the SnAs layers.},

keywords = {B4},

pubstate = {published},

tppubtype = {article}

}

@article{kollerSpinlatticeCouplingInduced2026,

title = {Spin-lattice coupling induced chiral phonons and their signature in Raman Circular Dichroism},

author = {E. Koller and S. Swarup and J. Knolle and N. B. Perkins},

url = {https://doi.org/10.1038/s41535-026-00893-5},

doi = {10.1038/s41535-026-00893-5},

year  = {2026},

date = {2026-06-17},

urldate = {2026-06-01},

journal = {npj Quantum Mater.},

volume = {11},

number = {1},

pages = {57},

note = {datadoi: 10.5281/zenodo.17437560},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{otsukiCompressedSensingCompton2026,

title = {Compressed Sensing of Compton Profiles for Fermi Surface Reconstruction: Concept and Implementation},

author = {J. Otsuki and K. Yoshimi and Y. Nakanishi-Ohno and M. Sekania and L. Chioncel and M. Mizumaki},

url = {https://doi.org/10.7566/JPSJ.95.074707},

doi = {10.7566/JPSJ.95.074707},

issn = {0031-9015},

year  = {2026},

date = {2026-06-15},

urldate = {2026-07-01},

journal = {J. Phys. Soc. Jpn.},

volume = {95},

number = {7},

pages = {074707},

abstract = {Compton scattering is a well-established technique that can provide detailed information about electronic states in solids. Making use of the principle of tomography, it is possible to determine the Fermi surface from sets of Compton-scattering data with different scattering axes. Practical applications, however, are limited due to the long acquisition time required for measuring along a sufficient number of scattering directions. Here, we propose to overcome this difficulty using compressed sensing. Taking advantage of a hidden sparsity in the momentum distribution, we are able to reconstruct the three-dimensional momentum distribution of bcc-Li, and identify the Fermi surface with as little as 14 directions of scattering data with unprecedented accuracy. This compressed-sensing approach will permit wider applications of the Compton scattering experiments.},

keywords = {A5},

pubstate = {published},

tppubtype = {article}

}

@article{ohanyanFlatBandsJ_1J_2J_32026,

title = {Flat bands in the J_{1}-J_{2}-J_{3} XXZ sawtooth chain},

author = {V. Ohanyan and J. Richter and M. Sekania and L. Giambattista and A. Andreanov and M. Kollar},

url = {https://link.aps.org/doi/10.1103/byv6-h2m2},

doi = {10.1103/byv6-h2m2},

year  = {2026},

date = {2026-06-04},

urldate = {2026-06-01},

journal = {Phys. Rev. B},

volume = {113},

number = {21},

pages = {214418},

abstract = {We consider a generalization of the XXZ model on the sawtooth spin chain with Dzyaloshinskii-Moriya interactions in which all exchange constants (symmetric, antisymmetric, and axial anisotropy) are different for the three different bonds of each triangle. We derive and resolve algebraic constraints on the exchange constants ensuring the appearance of a flat band in the one-magnon spectrum. The properties of the corresponding flat magnon bands and localized magnon states are analyzed. We further construct the mapping of the flat-band conditions for the Dzyaloshinskii-Moriya constants onto the Katsura-Nagaosa-Balatsky parameters. Based on the mapping, the possibility of the electric-field-driven flat bands with the aid of the magnetoelectric coupling is examined.},

keywords = {C4},

pubstate = {published},

tppubtype = {article}

}

@article{ishiharaCollinearFerromagnetismReduced2026-06-222026,

title = {Collinear ferromagnetism with reduced moment length in kagome magnet Nd_{3⁢}Ru_{4}⁢Al_{12}},

author = {Y. Ishihara and Ryota Nakano and R. Yamada and T. Nomoto and P. R. Baral and M. M. Hirschmann and K. Gautam and K. K. Kolincio and A. Kikkawa and S. Aji and H. Saitoh and M. Matsuda and Y. Taguchi and T. Arima and Y. Tokura and T. Nakajima and M. Hirschberger},

url = {http://dx.doi.org/10.1103/9pvl-33xc},

doi = {10.1103/9pvl-33xc},

issn = {2469-9969},

year  = {2026},

date = {2026-06-02},

urldate = {2026-06-01},

journal = {Phys. Rev. B},

volume = {113},

number = {21},

publisher = {American Physical Society (APS)},

abstract = {We determine the magnetic ground state of the kagome lattice magnet Nd3⁢Ru4⁢Al12 by single-crystal neutron diffraction, supported by experiments with polarized neutrons. We identify this material as a collinear ferromagnet (“hex-FM”) with uniform moment length and ordering vector Q=0, in contrast to a previous, seminal report that proposed unequal moment lengths on two Nd sites, here called the “ortho-FM” state. Our analysis of the flipping ratio in polarized neutron scattering is consistent with the hex-FM state. The results provide a microscopic basis for understanding the large fluctuation-induced Hall and Nernst responses near TC≈41K, as previously reported for Nd3⁢Ru4⁢Al12.},

keywords = {B5},

pubstate = {published},

tppubtype = {article}

}

@article{mangeolleDynamicalMagneticBreakdown2026,

title = {Dynamical magnetic breakdown and quantum oscillations from hot-spot scattering},

author = {L. Mangeolle and J. Knolle},

url = {https://link.aps.org/doi/10.1103/ytcj-6zkg},

doi = {10.1103/ytcj-6zkg},

year  = {2026},

date = {2026-06-01},

journal = {Phys. Rev. B},

volume = {113},

number = {24},

pages = {245132},

publisher = {American Physical Society},

abstract = {Quantum oscillations (QOs) are a well-established probe of Fermi-surface (FS) geometry and in the presence of long-range density wave order can display new QO frequencies from reconstructed FS pockets. We show that such reconstructed frequencies can arise even in the absence of long-range density order. Considering electrons coupled to a fluctuating bosonic mode that scatters quasiparticles between sharp hot spots on the FS, we develop a semiclassical theory in which the interaction generates time-dependent tunneling processes analogous to magnetic breakdown. This dynamical magnetic breakdown produces new semiclassical orbits corresponding to reconstructed FS areas despite the absence of static order. Because tunneling probabilities depend on the thermal population of bosonic excitations, the resulting oscillation amplitudes exhibit characteristic deviations from standard Lifshitz-Kosevich behavior. Our results provide a mechanism to probe bosonic fluctuations in quantum critical metals and provide a framework for dynamical magnetic breakdown.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{etoFateTopologicalDirac2026,

title = {Fate of Topological Dirac Magnons in van der Waals Ferromagnets at Finite Temperature},

author = {R. Eto and I. Salgado-Linares and M. Mochizuki and J. Knolle and A. Mook},

url = {https://link.aps.org/doi/10.1103/tbh2-jq9r},

doi = {10.1103/tbh2-jq9r},

year  = {2026},

date = {2026-06-01},

journal = {Phys. Rev. X},

volume = {16},

number = {2},

pages = {021053},

publisher = {American Physical Society},

abstract = {Dirac magnons, the bosonic counterparts of Dirac fermions in graphene, provide a versatile platform to explore symmetry-protected band crossings and quantum geometry in magnetic insulators while promising high-velocity, low-dissipation spin transport for next-generation magnonic technologies. However, their stability under realistic, finite-temperature conditions remains an open question. Here, we develop a microscopic theory of thermal magnon-magnon interactions in van der Waals honeycomb ferromagnets, focusing on both gapless and gapped Dirac magnons. Using nonlinear spin-wave theory with magnon self-energy corrections and a 𝑇-matrix resummation that captures two-magnon bound states, we quantitatively reproduce temperature- and momentum-dependent energy shifts and linewidths observed experimentally in the gapless Dirac magnon material CrBr3, even near the Curie temperature. Our approach provides a consistent interpretation of theoretical predictions and experiment shedding light on the role of bound states in enhancing magnon damping at low temperatures. For gapped Dirac magnon materials such as CrI3, CrSiTe3, and CrGeTe3, we find a thermally induced reduction of the topological magnon gap, while no indication of thermally driven topological phase transitions is observed within the considered parameter range. Classical atomistic spin-dynamics simulations corroborate the gap’s robustness up to the Curie temperature. Furthermore, we establish a practical criterion for observing topological gaps by determining the minimum ratio of Dzyaloshinskii-Moriya interaction to Heisenberg exchange required to overcome thermal broadening throughout the ordered phase, typically around 5%. Taken together, our results elucidate the interplay between thermal many-body effects and topology in low-dimensional magnetic systems and provide a controlled framework for the interpretation of spectroscopic measurements.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{waltherPersistenceBerezinskiiKosterlitzThoulessTransition2026,

title = {Persistence of the Berezinskii-Kosterlitz-Thouless Transition with Long-Range Couplings},

author = {L. Walther and J. Willsher and J. Knolle},

url = {https://link.aps.org/doi/10.1103/9y2v-ybdb},

doi = {10.1103/9y2v-ybdb},

year  = {2026},

date = {2026-06-01},

journal = {Phys. Rev. Lett.},

volume = {136},

number = {22},

pages = {227102},

publisher = {American Physical Society},

abstract = {The Berezinskii-Kosterlitz-Thouless (BKT) transition is an archetypal example of a topological phase transition, which is driven by the proliferation of vortices. In this Letter, we analyze the persistence of the BKT transition in the XY model under the influence of long-range algebraically decaying interactions of the form ∼1/𝑟2+𝜎. The model hosts a magnetized low temperature phase for sufficiently small 𝜎. Crucially, in the presence of long-range interactions, spin waves renormalize the interaction between vortices, which stabilizes the BKT transition. As a result, we find that there is no direct transition from the magnetized to the disordered phase and that the BKT transition persists for arbitrary long-range exponents, which is distinct from previous results. The key methodological advance is the inclusion of coupling between spin wave and topological excitations. We do this by developing Landau-Peierls–type arguments and using higher-order renormalization group calculations, obtaining compatible results. We emphasize that Landau-Peierls–type arguments are a powerful tool for analyzing continuous spin models. We discuss the relevance of our findings for current Rydberg atom experiments, and highlight the importance of long-range couplings for other types of topological defects.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{mukharjee2026anisotropicmagnetoelasticcouplinghoneycomb,

title = {Anisotropic magnetoelastic coupling in the honeycomb magnet Na_{3}Co_{2}SbO_{6}},

author = {P. K. Mukharjee and S. Erdmann and L. Wang and J. Kaiser and A. Jesche and P. Puphal and M. Isobe and M. Hepting and B. Keimer and P. Gegenwart and A. A. Tsirlin},

url = {https://doi.org/10.1103/tn1m-sjdh},

doi = {10.1103/tn1m-sjdh},

year  = {2026},

date = {2026-05-26},

urldate = {2026-05-26},

journal = {Phys. Rev. B},

volume = {113},

number = {20},

abstract = {We present magnetization and dilatometry measurements on the honeycomb cobaltate Na3⁢Co2⁢SbO6 and map out its detailed field-temperature phase diagram down to sub-Kelvin temperatures. Our data for in-plane magnetic fields show a strongly anisotropic 𝑐*-axis lattice response, which is dominated by the variation of Co–O–Co bond angles according to ab initio calculations. At 𝑇=0.4K, the magnetization 𝑀⁡(𝐵) exhibits steplike features that are also highly anisotropic. In the case of 𝐵∥𝑏, a small hysteresis observed around the second field-induced magnetic transition (𝐵𝑐⁢2) indicates its first-order character, whereas the apparent divergence of the magnetic Grüneisen parameter at 𝐵𝑐⁢2 is suppressed upon cooling and signals the absence of quantum critical behavior upon entering the field-polarized state. None of our thermodynamic measurements provide evidence for a field-induced quantum spin-liquid state near or above 𝐵𝑐⁢2.},

note = {datadoi: 10.5281/zenodo.18795732},

keywords = {B1, B2},

pubstate = {published},

tppubtype = {article}

}

@article{xl5f-zj9p,

title = {Three-dimensional XY universality and nonlinear magnetic susceptibility in a kagome ice compound},

author = {K. Zhao and H. Deng and H. Chen and N. Ma and N. Oefele and J. Guo and X. Cui and C. Tang and M. J. Gutmann and T. Mueller and Y. Su and V. Hutanu and C. Jin and P. Gegenwart},

url = {https://link.aps.org/doi/10.1103/xl5f-zj9p},

doi = {10.1103/xl5f-zj9p},

year  = {2026},

date = {2026-05-26},

urldate = {2026-05-01},

journal = {Phys. Rev. X},

volume = {16},

number = {2},

pages = {021043},

abstract = {Kagome spin ice is an intriguing class of spin systems constituted by in-plane Ising spins with ferromagnetic interaction residing on the kagome lattice, theoretically predicted to host a plethora of magnetic transitions and excitations. In particular, different variants of kagome spin ice models can exhibit different sequences of symmetry breaking upon cooling from the paramagnetic to the fully ordered ground state. Recently, it has been demonstrated that the frustrated intermetallic HoAgGe stands as a faithful solid-state realization of kagome spin ice. However, whether any of the established symmetry-breaking pathways apply to this material remains unaddressed. Here, we use single-crystal neutron diffuse scattering to map the spin ordering of HoAgGe at various temperatures more accurately; surprisingly, we find that the ordering sequence appears to be different from previously known scenarios: From the paramagnetic state, the system first enters a partially ordered state with fluctuating magnetic charges, in contrast to a charge-ordered paramagnetic phase, before reaching the fully ordered state. Through Monte Carlo simulations and scaling analyses using an extended three-dimensional (3D) spin model for the distorted kagome spin ice in HoAgGe, we elucidate a single 3D XY phase transition into the ground state with broken time-reversal symmetry (TRS). However, the 3D XY transition has a long crossover tail before the fluctuating magnetic charges fully order. More interestingly, we find, both experimentally and theoretically, that the TRS-breaking phase of HoAgGe features an unusual, hysteretic response: Despite their vanishing magnetization, the two time-reversal partners are distinguished and selected by a nonlinear magnetic susceptibility tied to the kagome ice rule. Our discovery not only unveils a new symmetry-breaking hierarchy of kagome spin ice but also demonstrates the potential of TRS-breaking frustrated spin systems for information technology applications.},

keywords = {B3},

pubstate = {published},

tppubtype = {article}

}

@article{toyodaAllopticalControlAntiferromagnetic2026,

title = {All-optical control of antiferromagnetic domains via an inverse optical magnetoelectric effect},

author = {S. Toyoda and V. Kocsis and Y. Tokunaga and I. Kézsmárki and Y. Taguchi and T. Arima and Y. Tokura and N. Ogawa},

url = {https://doi.org/10.1038/s41563-026-02608-4},

doi = {10.1038/s41563-026-02608-4},

year  = {2026},

date = {2026-05-15},

urldate = {2026-05-01},

journal = {Nat. Mater.},

volume = {25},

pages = {1572},

abstract = {All-optical control of antiferromagnetic order is essential for realizing next-generation energy-efficient spintronic and high-speed memory applications. However, the optical writing of antiferromagnetic domains remains a fundamental challenge, because conventional opto-magnetic recording techniques rely on net magnetization, which is absent in antiferromagnets. In certain multiferroic antiferromagnets, the magnetic toroidal moment provides an additional degree of freedom through its inherent magnetoelectric coupling, which manifests as directional asymmetry in light propagation. Here we demonstrate the all-optical writing of antiferromagnetic domains using the inverse optical magnetoelectric effect in ferrotoroidic LiNiPO4, driven solely by reversing the light propagation direction. This directional control arises from a strong coupling between the photon linear momentum and the magnetic toroidal moment, enabling non-volatile, deterministic and repeatable switching between time-reversed domains with arbitrary light polarization. Our findings establish an inverse optical magnetoelectric effect as a distinct mechanism for manipulating antiferromagnetic order, opening a new paradigm in opto-magnetism driven by photon momentum.},

note = {datadoi: 10.1038/s41563-026-02608-4},

keywords = {C2},

pubstate = {published},

tppubtype = {article}

}

@article{pichlerPurelyElectronicModel2026,

title = {Purely electronic model for exciton-polaron formation in moiré heterostructures},

author = {F. Pichler and M. Hafezi and M. Knap},

url = {https://doi.org/10.1103/98wg-qcfn},

doi = {10.1103/98wg-qcfn},

issn = {2643-1564},

year  = {2026},

date = {2026-05-11},

urldate = {2026-05-01},

journal = {Phys. Rev. Res.},

volume = {8},

number = {2},

publisher = {American Physical Society (APS)},

note = {datadoi: 10.5281/zenodo.14879210},

keywords = {C5, C6},

pubstate = {published},

tppubtype = {article}

}

@article{srivastavaTheoryNonlinearSpectroscopy2026,

title = {Theory of nonlinear spectroscopy of quantum magnets},

author = {A. Srivastava and S. Birnkammer and G. Sim and M. Knap and J. Knolle},

url = {https://link.aps.org/doi/10.1103/2rfx-8ql6},

doi = {10.1103/2rfx-8ql6},

year  = {2026},

date = {2026-05-07},

urldate = {2026-05-01},

journal = {Phys. Rev. B},

volume = {113},

number = {18},

pages = {184421},

publisher = {American Physical Society},

abstract = {Two-dimensional coherent spectroscopy (2DCS) is an established method for characterizing molecules and has been proposed in the terahertz regime as a tool for probing exotic excitations of quantum magnets; however, the precise nature of the coupling between pump field and spin degrees of freedom has remained unclear. Here, we develop a general response theory of 2DCS and show how magnetoelectric as well as polarization couplings contribute to 2DCS in addition to the typically assumed magnetization. We propose experimental protocols to probe the presence of polarization couplings, for instance, from exchange-striction or spin-current mechanism, when the electric field couples to quadratic terms in spin operators. We provide example calculations for the paradigmatic twisted Kitaev chain material CoNb2⁢O6 and highlight the crucial role of contributions from cross-coupling between polarization and magnetic nonlinear susceptibilities. Our work paves the way for systematic studies of light-matter couplings in quantum magnets and for establishing 2DCS as a versatile tool for probing fractional excitations of exotic magnetic quantum phases.},

note = {datadoi: 10.5281/zenodo.14938103},

keywords = {C6},

pubstate = {published},

tppubtype = {article}

}

@article{4z8z-4kch,

title = {Quantum geometric origin of the intrinsic nonlinear Hall effect},

author = {Y. Ulrich and J. Mitscherling and L. Classen and A. P. Schnyder},

url = {https://link.aps.org/doi/10.1103/4z8z-4kch},

doi = {10.1103/4z8z-4kch},

year  = {2026},

date = {2026-05-04},

urldate = {2026-05-01},

journal = {Phys. Rev. B},

volume = {113},

number = {20},

pages = {L201107},

abstract = {We decompose the intrinsic second-order nonlinear Hall effect (NLHE) of a generic multiband system into its quantum geometric contributions within a fully quantum-mechanical, projector-based formalism. By expanding the nonlinear conductivity in powers of the quasiparticle lifetime 𝜏, we recover the established Berry curvature dipole at order 𝜏 and clarify discrepancies in previous literature concerning the (interband) quantum metric dipole (or Berry curvature polarizability) contribution at order 𝜏0. Crucially, our method reveals an additional contribution at order 𝜏0, determined by the intraband quantum metric dipole (intraQMD), arising from additional virtual interband transitions captured within the fully quantum-mechanical treatment. The intraQMD contribution is generically nonzero in systems with broken time-reversal symmetry and can be distinguished from other geometric contributions by symmetry. Analytical results for low-energy models of topological band crossings, which are hot spots of quantum geometry, demonstrate how band topology influences each contribution. In particular, the intraQMD contribution is especially large in gapped Dirac cones in antiferromagnets. Through a comprehensive symmetry classification of all magnetic space groups, we identify several candidate materials that are expected to exhibit large intrinsic NLHE, including the topological antiferromagnets Yb3⁢Pt4, CuMnAs, and CoNb3⁢S6, as well as the nodal-plane material MnNb3⁢S6.},

keywords = {A6},

pubstate = {published},

tppubtype = {article}

}

@article{hirrleTuningJahnTellerDistortions2026,

title = {Tuning of Jahn-Teller distortions via sterically enforced lattice enlargement of Cu(ta)_{2}-type coordination polymers},

author = {M. Hirrle and R. Röß-Ohlenroth and S. Reschke and B. Bredenkötter and H. -A. Krug von Nidda and D. Volkmer},

url = {https://www.sciencedirect.com/science/article/pii/S0022369726000521},

doi = {10.1016/j.jpcs.2026.113566},

year  = {2026},

date = {2026-05-01},

urldate = {2026-05-01},

journal = {J. Phys. Chem. Solids.},

volume = {212},

pages = {113566},

abstract = {The control of Jahn-Teller distortions in copper-based coordination polymers is crucial for tuning their magnetic and structural properties. Here, we report the synthesis and characterization of two novel Cu(II)-based metal-organic frameworks (MOFs), Cu(mta)2 and Cu(cta)2, derived from modified triazole ligands. By introducing steric bulk through methyl and cyclopentyl substituents, we systematically investigate the effect of lattice enlargement on local coordination environments and magnetic behaviour. Single-crystal and powder X-ray diffraction analyses reveal that Cu(mta)2 exhibits static Jahn-Teller distortions similar to those observed in Cu(ta)2, whereas Cu(cta)2 crystallizes in an undistorted, near-ideal cubic structure. Magnetic susceptibility and electron spin resonance measurements show strong antiferromagnetic interactions and temperature-dependent g-factor anisotropy for Cu(ta)2 and Cu(mta)2, while Cu(cta)2 displays nearly isotropic magnetic behavior and only dynamically JT distortions without a cooperative phase transition. These results demonstrate that steric ligand design offers a powerful strategy to modulate the interplay between lattice structure and magnetic anisotropy. Our findings provide fundamental insights into the suppression of cooperative static Jahn-Teller distortions and open pathways for the targeted design of multifunctional MOFs with tailored structural and magnetic properties.},

keywords = {B4},

pubstate = {published},

tppubtype = {article}

}

@article{haghshenasDigitalQuantumMagnetism2026,

title = {Digital quantum magnetism on a trapped-ion quantum computer},

author = {R. Haghshenas and E. Chertkov and M. Mills and W. Kadow and S. -H. Lin and Y. H. Chen and C. Cade and I. Niesen and T. Begušić and M. S. Rudolph and C. Cirstoiu and K. Hémery and C. Mc Keever and M. Lubasch and E. Granet and C. H. Baldwin and J. P. Bartolotta and M. Bohn and J. J. Burau and J. Cline and M. DeCross and J. M. Dreiling and C. Foltz and D. Francois and J. P. Gaebler and C. N. Gilbreth and J. Gray and D. Gresh and A. Hall and A. Hankin and A. Hansen and N. Hewitt and C. A. Holliman and R. B. Hutson and M. Iqbal and N. Kotibhaskar and E. Lehman and D. Lucchetti and I. S. Madjarov and K. Mayer and A. R. Milne and S. A. Moses and B. Neyenhuis and G. Park and A. R. Perry and B. Ponsioen and M. Schecter and P. E. Siegfried and D. T. Stephen and B. G. Tiemann and M. D. Urmey and J. Walker and A. C. Potter and D. Hayes and G. K. -L. Chan and F. Pollmann and M. Knap and H. Dreyer and M. Foss-Feig},

url = {https://doi.org/10.1038/s41586-026-10445-3},

doi = {10.1038/s41586-026-10445-3},

issn = {1476-4687},

year  = {2026},

date = {2026-04-29},

urldate = {2026-04-01},

journal = {Nature},

volume = {653},

number = {8113},

pages = {56–62},

publisher = {Springer Science and Business Media LLC},

note = {datadoi: 10.5281/zenodo.18487089},

keywords = {C5, C6},

pubstate = {published},

tppubtype = {article}

}

@article{ynnr-dm9r,

title = {Magnetic transitions in the spin-5/2 triangular lattice antiferromagnet Ba_{3}MnTa_{2}O_{9}},

author = {S. P. Patra and S. Mohanty and S. Samanta and J. K. Oommen and A. A. Tsirlin and R. Nath},

url = {https://link.aps.org/doi/10.1103/ynnr-dm9r},

doi = {10.1103/ynnr-dm9r},

year  = {2026},

date = {2026-04-28},

urldate = {2026-04-28},

journal = {Phys. Rev. B},

volume = {113},

number = {14},

pages = {144436},

publisher = {American Physical Society},

abstract = {We report a comprehensive study of the structural and magnetic properties of the two-dimensional 𝑆=5/2 frustrated triangular-lattice antiferromagnet Ba3⁢MnTa2⁢O9 using x-ray diffraction, magnetization, electron spin resonance, and heat-capacity measurements on a polycrystalline sample, combined with density-functional band-structure calculations. The magnetic susceptibility and heat-capacity data reveal the onset of antiferromagnetic long-range order at 𝑇N≃2.6K, which is in sharp contrast with the recent report by Mondal et al. [Phys. Rev. B 112, 155153 (2025)] who did not observe magnetic order in this material. The nearest-neighbor exchange coupling 𝐽/𝑘B≃0.85K is obtained from Monte Carlo fits to the experimental susceptibility data. Combined with the ab initio estimate of the interlayer coupling, this 𝐽/𝑘B value leads to 𝑇N≃2.7K in a perfect agreement with the experiment. Magnetic isotherms reveal a field-induced transition below 𝑇N. The complex 𝐻−𝑇 phase diagram features multiple phases as a consequence of magnetic frustration and anisotropy present in the system.},

keywords = {B3},

pubstate = {published},

tppubtype = {article}

}

@article{nandiNovelQuantumSpin2025,

title = {Novel Quantum Spin Liquid States in the S = 1/2 Three-Dimensional Compound Y_{3}Cu_{2}Sb_{3}O_{14}},

author = {S. Nandi and R. Das and M. Hemmida and M.  U. Akbar and H. -A. Krug von Nidda and J. Sichelschmidt and S. Mahapatra and M. Schuller and N. Büttgen and J. Wilkinson and M. P. Saravanan and I. Dasgupta and A. V. Mahajan},

url = {https://doi.org/10.1103/2bps-xvl8},

doi = {10.1103/2bps-xvl8},

year  = {2026},

date = {2026-04-22},

urldate = {2026-04-01},

journal = {Phys. Rev. Lett.},

volume = {136},

pages = {166502},

abstract = {The three-dimensional S=1/2 system Y3⁢Cu2⁢Sb3⁢O14 consists of two inequivalent Cu2+ sites, each forming an edge shared triangular lattice. Our magnetic susceptibility 𝜒⁡(𝑇), specific heat 𝐶𝑝⁡(𝑇), 89Y nuclear magnetic resonance (NMR), muon spin relaxation (μ⁢SR), and electron spin resonance (ESR) measurements on this system confirm the absence of any long-range magnetic ordering and the persistence of spin dynamics down to 0.077 K. In 89Y NMR, we find an anomaly at about 120 K, which we suggest arises from a fraction of the spins condensing into a singlet (a valence bond solid, or VBS) state. A plateau in the muon relaxation rate is observed between 60 K and 10 K (signifying the VBS state from a fraction of the spins) followed by an increase and another plateau below about 1 K (presumably signifying the quantum spin liquid state from all the spins). Our density functional theory calculations find a dominant antiferromagnetic interaction along the body diagonal with inequivalent Cu(1) and Cu(2) ions alternately occupying the corners of the cube. All other near-neighbor interactions between the Cu ions are also found to be antiferromagnetic and are thought to drive the frustration.},

keywords = {B4},

pubstate = {published},

tppubtype = {article}

}

@article{yunStripeAntiferromagnetismVan2026,

title = {Stripe antiferromagnetism in the van der Waals metal HoTe_{3} decoupled from charge density wave order},

author = {W. Yun and R. Nakano and R. Misawa and R. Yamada and S. Akatsuka and Y. Ōnuki and P. R. Baral and S. Esser and H. Saitoh and R. Kiyanagi and T. Ohhara and T. Nakajima and T. Arima and M. Hirschberger},

url = {https://link.aps.org/doi/10.1103/q39f-b32w},

doi = {10.1103/q39f-b32w},

year  = {2026},

date = {2026-04-21},

urldate = {2026-04-01},

journal = {Phys. Rev. B},

publisher = {American Physical Society},

abstract = {The RTe3 (R = rare earth) family of layered van der Waals (vdW) compounds hosts coexisting magnetic and charge density wave (CDW) orders, yet the interplay between these degrees of freedom remains largely unexplored. Combining polarized and unpolarized neutron diffraction on single crystals of HoTe3, we identify two distinct antiferromagnetic (AFM) phases, both exhibiting a collinear ↑↑↓↓ motif within individual vdW layers. The two phases are distinguished by the vdW stacking of magnetic layers: ferromagnetic (FM) stacking in the higher-temperature AFM-II phase, here termed “vertical-stripe”, and AFM stacking in the AFM-I ground state, here termed “tilted-stripe”; the two phases have propagation vectors qm2 = (0.48, 0, 0) and qm1 = (0.5, 0.5, 0), respectively. In contrast to the CDW-driven exotic magnetism in DyTe3, TbTe3, and GdTe3, we find no evidence for coupling between magnetism and CDW in HoTe3. The presence of a checkerboard-type charge order in HoTe3 may be detrimental for realizing coupled spin/charge order parameters in layered vdW systems.},

keywords = {B5},

pubstate = {published},

tppubtype = {article}

}

@article{rojewskiOpticalResponseDirac2026,

title = {Optical response of the Dirac semimetals GdSb_{0.56}Te_{1.35} and GdSb_{0.45}Te_{1.50}: Influence of charge density wave distortion and magnetic order},

author = {S. Rojewski and R. Borkenhagen and R. Li and D. G. Ovalle and S. S. Tsirkin and H. Kumar and K. Raju and R. Sankar and S. Lei and L. M. Schoop and M. G. Vergniory and C. A. Kuntscher},

url = {https://link.aps.org/doi/10.1103/nygm-n4fv},

doi = {10.1103/nygm-n4fv},

year  = {2026},

date = {2026-04-20},

urldate = {2026-04-01},

journal = {Phys. Rev. B},

volume = {113},

number = {15},

pages = {155141},

abstract = {The square-net materials GdSb𝑥⁢Te2−𝑥−𝛿 

provide a platform for exploring the effects of charge density wave (CDW) distortion and band filling on the topological electronic band structure. In this work we use infrared spectroscopy to probe the temperature-dependent electronic excitations in GdSb0.56⁢Te1.35 and GdSb0.45⁢Te1.50 

single crystals for different polarization directions parallel to the square-net layers. First-principles calculations were also performed to study the electronic band structure and interband optical conductivity of stoichiometric GdSbTe. For GdSb0.56⁢Te1.35 the in-plane optical conductivity is independent of the polarization direction and contains a small Drude term, indicating a weak metallic character, and a pronounced near-infrared absorption band, which may be due to excitations across the CDW gap. Upon cooling, the optical response shows no significant temperature dependence within the experimental uncertainty, and no signatures associated with magnetic ordering are detected. In comparison, for GdSb0.45⁢Te1.50 we observe an in-plane anisotropy and strongly reduced low-frequency optical conductivity, with small temperature dependence. Possible signatures of Dirac fermion excitations in the optical conductivity spectra are also analyzed and discussed. Our results demonstrate that small differences in the stoichiometry have a significant impact on the optical response of GdSb𝑥⁢Te2−𝑥−𝛿 materials.},

note = {datadoi: (10.5281/zenodo.19235004)},

keywords = {A1},

pubstate = {published},

tppubtype = {article}

}

@article{pichlerFalseVacuumDecay2026,

title = {False Vacuum Decay in Flat-Band Ferromagnets: Role of Quantum Geometry and Chiral Edge States},

author = {F. Pichler and C. Kuhlenkamp and M. Knap},

url = {https://doi.org/10.1103/q7ss-pvcq},

doi = {10.1103/q7ss-pvcq},

issn = {1079-7114},

year  = {2026},

date = {2026-04-15},

urldate = {2026-04-01},

journal = {Phys. Rev. Lett.},

volume = {136},

number = {15},

publisher = {American Physical Society (APS)},

note = {datadoi: 10.5281/zenodo.17924292},

keywords = {C5, C6},

pubstate = {published},

tppubtype = {article}

}

@article{liefferinkEffectiveTheoryUltrafast2026,

title = {Effective Theory of Ultrafast Skyrmion Nucleation},

author = {R. Liefferink and L. Körber and K. Gerlinger and B. Pfau and F. Büttner and J. H. Mentink},

url = {https://link.aps.org/doi/10.1103/brnt-2m9l},

doi = {10.1103/brnt-2m9l},

issn = {0031-9007, 1079-7114},

year  = {2026},

date = {2026-04-10},

urldate = {2026-04-10},

journal = {Phys. Rev. Lett.},

volume = {136},

number = {14},

pages = {146705},

note = {datadoi: 10.34973/5168-bn56},

keywords = {C2},

pubstate = {published},

tppubtype = {article}

}

@article{ranautCrystalFieldScheme2026,

title = {Crystal field scheme and field-induced critical behavior in effective spin-1/2 NdVO_{4}},

author = {D. Ranaut and D. T. Adroja and M. Aouane and P. K. Mukharjee and P. Gegenwart and D. Jaiswal-Nagar},

url = {https://link.aps.org/doi/10.1103/c6v8-vx4h},

doi = {10.1103/c6v8-vx4h},

year  = {2026},

date = {2026-04-07},

urldate = {2026-04-04},

journal = {Phys. Rev. B},

volume = {113},

number = {14},

pages = {144411},

publisher = {American Physical Society},

abstract = {Quantum fluctuations in low-spin (𝑆=1/2) systems make them potential materials to investigate various intriguing field-induced quantum phenomena. In this context, rare-earth (4⁢𝑓)-based effective spin (𝐽eff=1/2) systems with localized magnetic moments and low energy scales offer an advantage of low critical fields and provide access to probe the complete magnetic phase diagram. Here, we present inelastic neutron scattering (INS) data to understand the crystal field (CF) scheme of the previously established 𝐽eff=1/2 antiferromagnet NdVO4, along with low-temperature magnetization and heat capacity measurements to construct the complete magnetic phase diagram. Our INS data validate the presence of the 𝐽eff=1/2 state at low temperatures with the ground and first excited CF state separated by an energy of 140 K. Furthermore, it yields a unique CF scheme where the excitation corresponding to the highest (fourth) CF state is observed via transitions involving the first and second excited states. Magnetic and heat capacity measurements yield the presence of a field-induced first-order spin-flop transition within the second-order antiferromagnetic (AFM) state. Magnetic phase diagrams constructed using the field-dependent magnetization and magnetic heat capacity reveal a continuous transformation from AFM to spin-flop state with a critical field of 𝐻sf∼1.4T. The presence of quantum fluctuations near 𝐻sf are evident from the V-shaped region in entropy contours indicating the presence of accumulated entropy.},

keywords = {B3},

pubstate = {published},

tppubtype = {article}

}

@article{koraltanMagneticForceMicroscopy2026,

title = {Magnetic Force Microscopy Signatures of Higher‐Order Skyrmions and Antiskyrmions},

author = {S. Koraltan and J. Sunny and T. Karaman and R. Peremadathil‐Pradeep and E. Darwin and F. Büttner and D. Suess and H. J. Hug and M. Albrecht},

url = {http://dx.doi.org/10.1002/adfm.202525716},

doi = {10.1002/adfm.202525716},

year  = {2026},

date = {2026-03-13},

urldate = {2026-03-13},

journal = {Adv. Funct. Mater.},

volume = {36},

number = {41},

publisher = {Wiley},

abstract = {Higher-order skyrmions and antiskyrmions are topologically protected spin textures with integer topological charges beyond 

±1, typically nucleating from vertical Bloch lines in domain walls. Until now, they have been reported only in ferromagnetic multilayers by Lorentz transmission electron microscopy (LTEM), which requires growth on ultrathin membranes and complicates their integration into spintronic devices. Moreover, LTEM often yields contrast patterns that are difficult to unambiguously assign to specific topological charges. Here, we demonstrate that magnetic force microscopy (MFM) operated under vacuum conditions provides a robust route to identify and distinguish higher-order spin textures in Co/Ni multilayers at room temperature. Supported by micromagnetic simulations, we show that MFM can resolve vertical Bloch lines as well as skyrmions and antiskyrmions with arbitrary charge. Our results establish advanced MFM as a powerful technique for the qualitative classification of complex spin textures, paving the way for their exploration and utilization in future skyrmionic device concepts.},

keywords = {A2, C2},

pubstate = {published},

tppubtype = {article}

}

@article{pichlerMicroscopicMechanismAnyon2026,

title = {Microscopic mechanism of anyon superconductivity emerging from fractional Chern insulators},

author = {F. Pichler and C. Kuhlenkamp and M. Knap and A. Vishwanath},

url = {https://doi.org/10.1016/j.newton.2025.100340},

doi = {10.1016/j.newton.2025.100340},

issn = {2950-6360},

year  = {2026},

date = {2026-03-02},

urldate = {2026-03-01},

journal = {Newton},

volume = {2},

number = {3},

pages = {100340},

publisher = {Elsevier BV},

note = {datadoi: 10.5281/zenodo.15594496},

keywords = {C5, C6},

pubstate = {published},

tppubtype = {article}

}

@article{davenportBerryCurvatureLowenergy2026,

title = {Berry curvature of low-energy excitons in rhombohedral graphene},

author = {H. Davenport and F. Schindler and J. Knolle},

url = {https://link.aps.org/doi/10.1103/shrm-4swg},

doi = {10.1103/shrm-4swg},

year  = {2026},

date = {2026-03-01},

journal = {Phys. Rev. B},

volume = {113},

number = {11},

pages = {115102},

publisher = {American Physical Society},

abstract = {We investigate low-energy excitons in rhombohedral pentalayer graphene encapsulated by hexagonal boron nitride (hBN/R5G/hBN), focusing on the regime at the experimental twist angle 𝜃=0.77° and with an applied electric field. We introduce a new low-energy two-band model of rhombohedral graphene that captures the band structure more accurately than previous models while keeping the number of parameters low. Using this model, we show that the centres of the exciton Wannier functions are displaced from the moiré unit cell origin by a quantized amount—they are instead localized at 𝐶3-symmetric points on the boundary. We also find that the exciton shift is electrically tunable: by varying the electric field strength, the exciton Wannier center can be exchanged between inequivalent corners of the moiré unit cell. Our results suggest the possibility of detecting excitonic corner or edge modes, as well as novel excitonic crystal defect responses in hBN/R5G/hBN. Lastly, we find that the excitons in hBN/R5G/hBN inherit excitonic Berry curvature from the underlying electronic bands, enriching their semiclassical transport properties. Our results position rhombohedral graphene as a compelling tunable platform for probing exciton topology in moiré materials.},

note = {datadoi: 10.5281/zenodo.16902666},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{mangeolleExtrinsicContributionBosonic2026,

title = {Extrinsic Contribution to Bosonic Thermal Hall Transport},

author = {L. Mangeolle and J. Knolle},

url = {https://link.aps.org/doi/10.1103/grzx-v6sj},

doi = {10.1103/grzx-v6sj},

year  = {2026},

date = {2026-03-01},

journal = {Phys. Rev. X},

volume = {16},

number = {1},

pages = {011048},

publisher = {American Physical Society},

abstract = {Bosonic excitations like phonons and magnons dominate the low-temperature transport of magnetic insulators. Similar to electronic Hall responses, the thermal Hall effect (THE) of charge-neutral bosons has been proposed as a powerful tool for probing topological properties of their wave functions. For example, the intrinsic contribution of the THE of a perfectly clean system is directly governed by the distribution of Berry curvature, and many experiments on topological magnon and phonon insulators have been interpreted in this way. However, disorder is inevitably present in any material, and its contribution to the THE has remained poorly understood. Here, we develop a rigorous kinetic theory of the extrinsic side-jump contribution to the THE of bosons. We show that the extrinsic THE is always relevant for bosonic systems and can be of the same order as the intrinsic one but sensitively depends on the type of local imperfection. We study different types of impurities and show that a THE can even arise as a pure impurity-induced effect in a system with a vanishing intrinsic contribution. As a side product, we also generalize existing results for the electronic anomalous Hall effect to general types of impurities beyond the standard assumption of local potential scattering. We discuss the importance of our results for the correct interpretation of THE measurements, for example, in the Kitaev magnet 𝛼−RuCl3, and provide a ready-to-use formula for comparison to experimental data.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nakanoPerfectlyHarmonicSpin2026,

title = {Perfectly harmonic spin cycloid and multi-Q textures in the Weyl semimetal GdAlSi},

author = {R. Nakano and R. Yamada and J. Bouaziz and M. Colling and M. Gen and K. Shoriki and Y. Okamura and A. Kikkawa and R. Misawa and P. R. Baral and S. Kitou and Y. Nakamura and H. Ohsumi and Y. Tanaka and H. Sagayama and H. Nakao and Y. Ishihara and K. Gautam and O. Fabelo and Y. Taguchi and Y. Takahashi and M. Tokunaga and T. Arima and Y. Tokura and R. Arita and J. Masell and S. Hayami and M. Hirschberger},

url = {http://dx.doi.org/10.1038/s41467-026-69452-7},

doi = {10.1038/s41467-026-69452-7},

issn = {2041-1723},

year  = {2026},

date = {2026-02-23},

urldate = {2026-02-01},

journal = {Nat. Commun.},

volume = {17},

number = {1},

publisher = {Springer Science and Business Media LLC},

abstract = {A fundamental question in condensed matter physics concerns how topological electronic states are influenced by many-body correlations, and magnetic Weyl semimetals represent an important material platform to address this problem. However, the magnetic structures realized in these materials are limited, and in particular, no clear example of an undistorted helimagnetic state has been definitively identified. Here, we report clear evidence of a harmonic helimagnetic cycloid with an incommensurate magnetic propagation vector Q in the Weyl semimetal GdAlSi via resonant elastic X-ray scattering, including rigorous polarization analysis. This cycloidal structure is consistent with the Dzyaloshinskii–Moriya interaction prescribed by the polar crystal structure of GdAlSi. Upon applying a magnetic field, the cycloid undergoes a transition to a novel multi-Q state. This field-induced, noncoplanar texture is consistent with our numerical spin model, which incorporates the Dzyaloshinskii–Moriya interaction and, crucially, anisotropic exchange interactions. The perfectly harmonic Weyl helimagnet GdAlSi serves as a prototypical platform to study electronic correlation effects in periodically modulated Weyl semimetals.},

note = {datadoi: 10.5281/zenodo.18228967},

keywords = {B5},

pubstate = {published},

tppubtype = {article}

}

@article{yamaguchiTopologicalThermalHall2026,

title = {Topological thermal Hall effect and nondissipative transport of the nanometric skyrmion lattice in Gd_{2}PdSi_{3}},

author = {D. Yamaguchi and P. Mokhtari and R. Yamada and A. Kikkawa and Y. Taguchi and Y. Tokura and M. Hirschberger},

url = {http://dx.doi.org/10.1093/pnasnexus/pgag041},

doi = {10.1093/pnasnexus/pgag041},

issn = {2752-6542},

year  = {2026},

date = {2026-02-23},

urldate = {2026-02-01},

journal = {PNAS Nexus},

volume = {5},

number = {3},

publisher = {Oxford University Press (OUP)},

abstract = {We report the first observation of a topological thermal Hall effect (tTHE) of electrons moving through a magnetic skyrmion lattice (SkL) of short period, where the skyrmion diameter is only a few nanometers. In the hexagonal intermetallic Gd2PdSi3, we observe a characteristic anomaly in the magnetic field dependence of the thermal Hall conductivity κxy, which scales well with the anomaly in the electrical Hall conductivity σxy and is closely related to the topological winding number of the SkL ground state. The relative magnitude of entropy and charge currents, defined as the Lorenz ratio ∼κxy/(σxyT), is consistent with a nondissipative, or intrinsic, mechanism for the topological Hall effect. We stress that the Berry phase in momentum space (k-space) causes such a nondissipative Hall transport, independent of the carrier relaxation time.},

keywords = {B5},

pubstate = {published},

tppubtype = {article}

}

@article{shaoElectricfieldTunableAnisotropic2026,

title = {Electric-field tunable anisotropic g-Factor induced by spin pumping},

author = {J. Shao and M. Kronseder and J. Guo and M. Mangold and D. Pan and T. N. G. Meier and W. Zhao and J. Zhao and C. H. Back and L. Chen},

url = {http://dx.doi.org/10.1021/acs.nanolett.5c05536},

doi = {10.1021/acs.nanolett.5c05536},

issn = {1530-6992},

year  = {2026},

date = {2026-02-20},

urldate = {2026-02-01},

journal = {Nano Letters},

volume = {26},

number = {8},

pages = {2853–2860},

publisher = {American Chemical Society (ACS)},

abstract = {Spin pumping, a well-established phenomenon where the precessing magnetization of a ferromagnet (FM) injects a pure spin current into an adjacent nonmagnetic layer, is characteristically identified by the enhancement of magnetic damping in the FM. Theoretical work has also suggested that spin pumping can affect the Landé g-factoranother key parameter of ferromagnetic materials besides the magnetic damping. However, experimental evidence of this effect has remained limited. Here, we demonstrate that spin pumping can lead to significant modulation of the g-factor in a Py/AlOx/STO two-dimensional electron gas (2DEG) system with strong spin–orbit interaction. Specifically, we observe an anisotropic g-factor with 2-fold symmetry below the onset temperature of the 2DEG, and furthermore this anisotropy can be tuned when applying an external electric field. This work uncovers a previously overlooked effect and offers new possibilities for controlling magnetization dynamics in systems with a reduced dimension.},

keywords = {A2},

pubstate = {published},

tppubtype = {article}

}

@article{schilberthOpticalPhononsTesting2025,

title = {Optical phonons as a testing ground for spin group symmetries},

author = {F. Schilberth and M. Kondákor and D. Ukolov and A. Pawbake and K. Vasin and O. Ercem and L. Prodan and V. Tsurkan and A. A. Tsirlin and C. Faugeras and P. Lemmens and K. Penc and I. Kézsmárki and S. Bordács and J. Deisenhofer},

url = {https://doi.org/10.1038/s41535-026-00857-9},

doi = {0.1038/s41535-026-00857-9},

year  = {2026},

date = {2026-02-17},

urldate = {2026-02-01},

journal = {npj Quantum Mater.},

volume = {11},

pages = {26},

abstract = {Lattice vibrations are highly sensitive to crystal symmetries and their changes across phase transitions. The latter can modify irreducible (co)representations and corresponding infrared and Raman selection rules of phonons. This concept is established for relativistic magnetic point groups, simultaneously transforming spatial and spin coordinates. However, in altermagnets described by non-relativistic spin groups with disjunct symmetry operations for both vector spaces, the phonon selection rules have remained unexplored. Here, we present a detailed study of the infrared- and Raman-active modes in the collinear antiferromagnet and altermagnet candidate Co2Mo3O8. Comparing to ab initio calculations accurately capturing the eigenfrequencies, we identify all expected phonon modes at room temperature and deduce their selection rules using both symmetry approaches. Importantly, we observe the change of selection rules upon antiferromagnetic ordering, agreeing with the relativistic symmetry approach, while the spin group formalism predicts no changes. Therefore, optical phonons sensing the symmetry of the magnetic order can reveal if relevant magnon-phonon coupling is compatible with the spin-group approach or not.},

note = {datadoi: 10.5281/zenodo.16751739},

keywords = {B1, C4},

pubstate = {published},

tppubtype = {article}

}

@article{kuchlerHighresolutionCapacitanceDilatometry2026,

title = {High-resolution capacitance dilatometry of microscopically thin samples using a miniature dilatometer},

author = {R. Küchler and S. N. Panja and S. Wirth and P. Gegenwart},

url = {https://doi.org/10.1063/5.0300507},

doi = {10.1063/5.0300507},

issn = {0034-6748},

year  = {2026},

date = {2026-02-12},

urldate = {2026-02-01},

journal = {Rev. Sci. Instrum.},

volume = {97},

number = {2},

pages = {025209},

abstract = {We present a novel application of our high-resolution capacitance dilatometer, specifically engineered for the precise characterization of quantum materials. These materials, which often appear as ultrathin, platelet-shaped crystals, are known for exotic phenomena such as superconductivity, topological order, and quantum spin liquid. However, these crystals seldom reach macroscopic dimensions, making them unsuitable for conventional dilatometry techniques. By introducing a modified sample-mounting configuration, our design enables high-resolution measurements of thermal expansion and magnetostriction along in-plane crystallographic directions in samples with thicknesses well below 500 μm. Validation measurements using a Quantum Design PPMS system confirm reliable performance for a 300 μm-thick silver platelet, relatively hard ferromagnetic EuB6 single crystals down to 50 μm, and a 40 μm-thin, soft AgCrS2 single crystal. This advancement significantly broadens the applicability of capacitance dilatometry, providing a powerful platform for investigating emergent phenomena in reduced-dimensional quantum systems.},

keywords = {B1, B3},

pubstate = {published},

tppubtype = {article}

}

@article{ohanyanElectricfieldDrivenFlat2026,

title = {Electric-field driven flat bands in the distorted sawtooth chain via the Katsura–Nagaosa–Balatsky mechanism},

author = {V. Ohanyan and L. Amiraghyan and M. Sekania and M. Kollar},

url = {https://doi.org/10.1515/zna-2025-0381},

doi = {doi:10.1515/zna-2025-0381},

year  = {2026},

date = {2026-02-10},

urldate = {2026-02-01},

journal = {Z. Naturforsch. A},

volume = {81},

number = {4},

pages = {289},

abstract = {We investigate flat magnonic bands in a generalized sawtooth-chain model in which three sets of exchange parameters (symmetric Heisenberg exchange, axial Ising anisotropy, and antisymmetric Dzyaloshinskii–Moriya (DM) exchange) are assigned independently to each side of the triangular plaquette. If the effective Dzyaloshinskii–Moriya (DM) interaction parameters are generated via the Katsura–Nagaosa–Balatsky (KNB) mechanism of magnetoelectricity, they become explicit functions of the electric-field magnitude and direction, as well as of the lattice geometry, which in the present case is characterized by two bond angles. We focus on the situation in which these two angles are unequal, corresponding to a distortion of the triangular plaquette. Several electric-field–induced flat-band scenarios in the distorted sawtooth chain are analyzed, and expressions are derived for the electric-field strength required to drive the one-magnon excitations into a flat-band regime when the field is aligned along the lattice bonds. The saturation field and its dependence on the distortion angle are also examined. Finally, we establish a mapping between the flat-band solutions for a general DM interaction and its specific KNB-induced form.},

keywords = {C4},

pubstate = {published},

tppubtype = {article}

}

@article{gagglBulkSuperconductivityKagome2026,

title = {Bulk superconductivity in the kagome metal YRu_{3}B_{2}},

author = {T. Gaggl and R. Misawa and M. Kriener and Y. Tanaka and R. Yamada and M. Hirschberger},

url = {https://doi.org/10.1088/1402-4896/ae3c65},

doi = {10.1088/1402-4896/ae3c65},

year  = {2026},

date = {2026-02-05},

urldate = {2026-02-01},

journal = {Phys. Scr.},

volume = {101},

number = {5},

pages = {055912},

abstract = {Materials with a kagome lattice have been heavily studied for their exotic electronic band structure, geometrical frustration, high-temperature charge-order transitions, and unconventional electron-phonon coupling. In LaRu3Si2, it was proposed that electronic flat bands conspire with the characteristic phonon spectrum of the kagome lattice to drive enhanced superconductivity at Tc = 6.8 K. Here, we report bulk superconductivity in the structural analogue YRu3B2, which hosts a pristine kagome lattice. We observe a superconducting transition at Tc = 0.7 K through magnetization, resistivity, and heat-capacity measurements in this novel kagome metal.},

note = {datadoi: (10.5281/zenodo.18276372)},

keywords = {B5, C1},

pubstate = {published},

tppubtype = {article}

}

@article{weberNonreciprocalZoneBoundary2026,

title = {Nonreciprocal zone boundary magnon propagation in Cu_{2}OSeO_{3}},

author = {T. Weber and N. Heinsdorf and M. Stekiel and P. Steffens and A. P. Schnyder and C. Pfleiderer},

url = {https://link.aps.org/doi/10.1103/q77j-5g59},

doi = {10.1103/q77j-5g59},

year  = {2026},

date = {2026-01-29},

urldate = {2026-01-29},

journal = {Phys. Rev. B},

volume = {113},

number = {2},

pages = {L020414},

publisher = {American Physical Society},

abstract = {Inelastic neutron scattering in the chiral magnet Cu2⁢OSeO3 reveals strong nonreciprocal effects on magnon propagation at the boundary of the nuclear Brillouin zone. The nonreciprocal response is strongest at a central position between the zone corner and the edge midpoint. We explain these results using an effective linear spin-wave model. While directional effects in chiral magnets have so far only been known to exist at low momenta close to the center of the Brillouin zone, the present study shows that nonreciprocity persists at the highest possible reduced momenta. The observed magnons show very little damping within the limits of our experimental resolution, making them of great interest for the fundamental research on compact, high-frequency magnonic applications.},

note = {datadoi: 10.5281/zenodo.16600991},

keywords = {A6, C1},

pubstate = {published},

tppubtype = {article}

}

@article{gammon-smithSimulatingTopologicalOrder2026,

title = {Simulating topological order on quantum processors},

author = {A. Gammon-Smith and M. Knap and F. Pollmann},

url = {https://doi.org/10.1038/s42254-025-00911-8},

doi = {10.1038/s42254-025-00911-8},

issn = {2522-5820},

year  = {2026},

date = {2026-01-26},

urldate = {2026-01-01},

journal = {Nat. Rev. Phys.},

volume = {8},

number = {3},

pages = {160–170},

publisher = {Springer Science and Business Media LLC},

keywords = {C5, C6},

pubstate = {published},

tppubtype = {article}

}

@article{magarProximateSpinliquidBehavior2025,

title = {Proximate spin-liquid behavior in the double trillium lattice antiferromagnet K_{2}Co_{2}(SO_{4})_{3}},

author = {A. Magar and K. Somesh and M. P. Saravanan and J. Sichelschmidt and Y. Skourski and M. T. F. Telling and V. A. Ginga and A. A. Tsirlin and R. Nath},

url = {https://doi.org/10.1103/m8mj-slvl},

doi = {10.1103/m8mj-slvl},

year  = {2026},

date = {2026-01-16},

urldate = {2026-01-01},

journal = {Phys. Rev. B},

volume = {113},

number = {2},

pages = {L020409},

abstract = {We report proximate quantum spin liquid behavior in K2⁢Co2 (SO4)3 with the magnetic Co2+ ions embedded on a highly frustrated three-dimensional double trillium lattice. Single-crystal and high-resolution synchrotron powder x-ray diffraction experiments reveal a structural phase transition at 𝑇_t≃125K from high-temperature cubic to low-temperature monoclinic phase with the threefold superstructure. Magnetization and heat capacity consistently show the formation of the 𝐽eff=1/2 state of Co2+ below 50 K. In zero field, K2⁢Co2(SO4)3 shows signatures of static magnetic order formed below 𝑇*≃0.6K, but muon spin relaxation experiments reveal a large fluctuating component that persists down to at least 50 mK, reminiscent of quantum spin liquid (QSL). Static order is completely suppressed in the small magnetic field of ∼1T, and low-temperature heat capacity demonstrates the 𝑇2 behavior above this field, another fingerprint of QSL. Ab initio calculations show a competition of several antiferromagnetic couplings that render K2⁢Co2(SO4)3 a promising pseudospin-1/2 material for studying quantum magnetism in the double trillium lattice geometry.},

keywords = {B3},

pubstate = {published},

tppubtype = {article}

}

@article{yamadaEmergentElectricField2026,

title = {Emergent electric field induced by dissipative sliding dynamics of domain walls in a Weyl magnet},

author = {R. Yamada and D. Kurebayashi and Y. Fujishiro and S. Okumura and D. Nakamura and F. S. Yasin and T. Nakajima and T. Yokouchi and A. Kikkawa and Y. Taguchi and Y. Tokura and O. A. Tretiakov and M. Hirschberger},

url = {https://doi.org/10.1038/s41567-025-03124-z},

doi = {10.1038/s41567-025-03124-z},

year  = {2026},

date = {2026-01-15},

urldate = {2026-01-01},

journal = {Nat. Phys.},

volume = {22},

number = {2},

pages = {239–244},

abstract = {The dynamic motion of topological defects in magnets induces an emergent electric field, as exemplified by the continuous flow of skyrmion vortices. However, the electrodynamics underlying this emergent field remains poorly understood. In this context, magnetic domain walls—one-dimensional topological defects with two collective modes, sliding and spin-tilt—offer a promising platform for exploration. Here we demonstrate that the dissipative motion of domain walls under oscillatory current excitation generates an emergent electric field. We image domain patterns and quantify the domain-wall length under applied magnetic fields in mesoscopic devices based on the magnetic Weyl semimetal NdAlSi. These devices exhibit exceptionally strong domain-wall scattering and a pronounced emergent electric field, as observed in the imaginary component of the complex impedance. Spin dynamics simulations reveal that domain-wall sliding dominates over spin-tilting, in which the phase delay of the domain-wall motion with respect to the driving force impacts the emergent electric field. Our findings establish domain-wall dynamics as a platform for studying emergent electromagnetic fields and motivate further investigations of the coupled motion of magnetic solitons and conduction electrons.},

note = {datadoi: (10.5281/zenodo.17188494)},

keywords = {B5},

pubstate = {published},

tppubtype = {article}

}

@article{khodaevaQuantumCriticalDynamical2026,

title = {Quantum critical dynamical response of the twisted Kitaev spin chain},

author = {U. E. Khodaeva and D. L. Kovrizhin and J. Knolle},

url = {https://link.aps.org/doi/10.1103/884v-7tqh},

doi = {10.1103/884v-7tqh},

year  = {2026},

date = {2026-01-12},

urldate = {2026-01-01},

journal = {Phys. Rev. B},

volume = {113},

number = {4},

pages = {045120},

publisher = {American Physical Society},

abstract = {The dynamical structure factor of the transverse field Ising model (TFIM) shows universal power-law divergence at its quantum critical point, signatures of which have been arguably observed in inelastic neutron scattering studies of quantum spin chain materials, for example CoNb2⁢O6. However, it has recently been suggested that its microscopic description is better captured in terms of a twisted Kitaev spin chain (TKSC) with bond-anisotropic couplings. Here, we present exact results for the dynamical structure factor of the TKSC across its quantum critical point, analyzing both the universal low-frequency response and the non-universal high-energy features. In addition, we explore extensions of the model including broken glide symmetry as well as the case of random, and incommensurate magnetic fields. Notably, in the latter case, the fermionic excitations exhibit a localization-delocalization transition, which is manifest in the dynamical response as a distinct signature at finite frequency. We discuss the relevance of these features for the observation of quantum critical response in experiments.},

note = {datadoi: 10.5281/zenodo.15722856},

keywords = {B6},

pubstate = {published},

tppubtype = {article}

}

@article{winklerStrongMagnetocapacitanceAnomaly2026,

title = {Strong magnetocapacitance anomaly signals the onset of the magnetoelectric Néel-type antiferromagnetic order in Co_{3}O_{4}},

author = {M. Winkler and L. Prodan and V. Tsurkan and P. Lunkenheimer and I. Kézsmárki and S. Ghara},

url = {https://link.aps.org/doi/10.1103/d9tp-h4wz},

doi = {10.1103/d9tp-h4wz},

issn = {2469-9950, 2469-9969},

year  = {2026},

date = {2026-01-12},

urldate = {2026-01-12},

journal = {Phys. Rev. B},

volume = {113},

number = {2},

pages = {024409},

abstract = {The magnetoelectric antiferromagnet Co3⁢O4 has recently been reported as a promising platform for isothermal electric manipulation of antiferromagnetic states. Here, we report a detailed study on magnetization, heat capacity, dielectric properties, and electric polarization in single crystals of Co3⁢O4. Magnetization and heat capacity measurements affirm the occurrence of a Néel-type collinear antiferromagnetic ordering below its Néel temperature 𝑇N = 30 K, where the direction of the Néel vector can be rotated by weak fields. This magnetic ordering breaks the spatial inversion and time reversal symmetries and permits a strong linear magnetoelectric effect, leading to the emergence of field-induced electric polarization below 𝑇N, and is also manifested in a magnetic field-induced sharp 𝜆-like peak in the dielectric constant at 𝑇N. Notably, the corresponding magnetocapacitance reaches a maximum value as high as 110% close to 𝑇N. This magnetocapacitance exhibits a quadratic dependence on the strength of the applied magnetic field, which is discussed within the framework of a phenomenological Landau theory.},

note = {datadoi: 10.5281/zenodo.17878913},

keywords = {A4},

pubstate = {published},

tppubtype = {article}

}

@article{dornellasAltermagnetismCrystalSymmetry2026,

title = {Altermagnetism without crystal symmetry},

author = {P. d'Ornellas and V. Leeb and A. G. Grushin and J. Knolle},

url = {https://link.aps.org/doi/10.1103/zqnk-153f},

doi = {10.1103/zqnk-153f},

year  = {2026},

date = {2026-01-01},

journal = {Phys. Rev. B},

volume = {113},

number = {2},

pages = {024426},

publisher = {American Physical Society},

abstract = {Altermagnetism is a collinear magnetic order in which opposite spin species are exchanged under a real-space rotation. Hence, the search for physical realizations has focused on crystalline solids with specific rotational symmetry. Here, we show that altermagnetism can also emerge in noncrystalline systems, such as amorphous solids, despite the lack of global rotational symmetries. We construct a minimal Hamiltonian with two directional orbitals per site on an amorphous lattice with interactions that are invariant under spin rotation. Altermagnetism then arises due to spontaneous symmetry breaking in the spin and orbital degrees of freedom around each atom, displaying a common point group symmetry. This form of altermagnetism exhibits anisotropic spin transport and spin spectral functions, both experimentally measurable. Our mechanism generalizes to any lattice and any altermagnetic order, opening the search for altermagnetic phenomena to noncrystalline systems.},

note = {datadoi: https://github.com/dpreuo/alter_morph},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{davenportExcitonBerryology2026,

title = {Exciton Berryology},

author = {H. Davenport and J. Knolle and F. Schindler},

url = {https://link.aps.org/doi/10.1103/jtgq-vc7n},

doi = {10.1103/jtgq-vc7n},

year  = {2026},

date = {2026-01-01},

journal = {Phys. Rev. B},

volume = {113},

number = {4},

pages = {045125},

publisher = {American Physical Society},

abstract = {In translationally invariant semiconductors that host exciton bound states, one can define an infinite number of possible exciton Berry connections. These correspond to the different ways in which a many-body exciton state, at fixed total momentum, can be decomposed into free electron and hole Bloch states that are entangled by an exciton envelope wave function. Inspired by the modern theory of polarization, we define an exciton projected position operator whose eigenvalues single out two unique choices of exciton Berry phase and associated Berry connection—one for electrons, and one for holes. We clarify the physical meaning of these exciton Berry phases and provide a discrete Wilson loop formulation that allows for their numerical calculation without a smooth gauge. As a corollary, we obtain a gauge-invariant expression for the exciton polarization at a given total momentum, i.e., the mean separation of the electron and hole within the exciton wave function. In the presence of crystalline inversion symmetry, the electron and hole exciton Berry phases are quantized to the same value and we derive how this value can be expressed in terms of inversion eigenvalues of the many-body exciton state. We then consider 𝐶2⁢𝒯 symmetry, for which no symmetry eigenvalues are available as it is antiunitary, and confirm that the exciton Berry phase remains quantized and still diagnoses topologically distinct exciton bands. The notion of shift excitons, whose exciton Wannier states are displaced from those of the noninteracting bands by a quantized amount, can therefore be generalized beyond symmetry indicators.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{upadhyayGiantEnhancementExciton2026,

title = {Giant enhancement of exciton diffusion near an electronic Mott insulator},

author = {P. Upadhyay and D. G. Suárez-Forero and T. -S. Huang and M. J. Mehrabad and B. Gao and S. Sarkar and D. Session and K. Watanabe and T. Taniguchi and Y. Zhou and M. Knap and M. Hafezi},

url = {https://doi.org/10.1126/science.ads5266},

doi = {10.1126/science.ads5266},

issn = {1095-9203},

year  = {2026},

date = {2026-01-01},

urldate = {2026-01-01},

journal = {Science},

volume = {391},

number = {6783},

pages = {394–398},

publisher = {American Association for the Advancement of Science (AAAS)},

note = {datadoi: 10.5061/dryad.3r2280gv7},

keywords = {C5, C6},

pubstate = {published},

tppubtype = {article}

}

@article{klingerSub1AdiabaticDemagnetization2026,

title = {Sub-1 K Adiabatic Demagnetization Refrigeration with Rare-Earth Borates Ba_{3}XB_{9}O_{18} and Ba_{3}XB_{3}O_{9}, X = (Yb, Gd)},

author = {M. Klinger and T. Treu and F. Kreisberger and C. Heil and A. Klinger and A. Jesche and P. Gegenwart},

url = {https://doi.org/10.3390/app16010290},

doi = {10.3390/app16010290},

year  = {2025},

date = {2025-12-27},

urldate = {2026-01-01},

journal = {Appl. Sci.},

volume = {16},

number = {1},

pages = {290},

abstract = {Adiabatic demagnetization refrigeration (ADR) is regaining relevance for refrigeration to temperatures below 1 K as global helium-3 supply is increasingly strained. While ADR at these temperatures is long established with paramagnetic hydrated salts, more recently, frustrated rare-earth oxides were found to offer higher entropy densities and practical advantages, since they do not degrade under heating or evacuation. We report structural, magnetic, and thermodynamic properties of the rare-earth borates Ba3XB9O18 and Ba3XB3O9 with X = (Yb, Gd). Except for Ba3GdB9O18, which orders at 108 mK, the three other materials remain paramagnetic down to their lowest measured temperatures. ADR performance starting at 2 K in a field of 5 T is analyzed and compared to literature.},

note = {datadoi: 10.5281/zenodo.17855051},

keywords = {B3},

pubstate = {published},

tppubtype = {article}

}

@article{neehusProjectivelyImplementedAltermagnetism2025,

title = {Projectively Implemented Altermagnetism in an Exactly Solvable Quantum Spin Liquid},

author = {A. Neehus and A. Rosch and J. Knolle and U. F.  P. Seifert},

url = {https://link.aps.org/doi/10.1103/cnk8-vnxg},

doi = {10.1103/cnk8-vnxg},

year  = {2025},

date = {2025-12-19},

urldate = {2025-12-01},

journal = {Phys. Rev. Lett.},

volume = {135},

number = {25},

pages = {256504},

publisher = {American Physical Society},

abstract = {Altermagnets are a new class of symmetry-compensated magnets with large spin splittings. Here, we show that the notion of altermagnetism extends beyond the realm of Landau-type order: we study exactly solvable ℤ2 quantum spin(-orbital) liquids (QSLs), which simultaneously support magnetic long-range order as well as fractionalization and ℤ2 topological order. Our symmetry analysis reveals that in this model three distinct types of “fractionalized altermagnets (AM*)” emerge, which can be distinguished by their residual symmetries. Importantly, the fractionalized excitations of these states carry an emergent ℤ2 gauge charge, which implies that they transform projectively under symmetry operations. Consequently, we show that “altermagnetic spin splittings” are now encoded in a momentum-dependent particle-hole asymmetry of the fermionic parton bands. We discuss consequences for experimental observables such as dynamical spin structure factors and (nonlinear) thermal and spin transport.},

note = {datadoi: 10.5281/zenodo.15231830},

keywords = {B6},

pubstate = {published},

tppubtype = {article}

}

@article{shiotaniNearroomtemperatureCompensatedItinerant2025,

title = {Near-room-temperature compensated itinerant pyrochlore ferrimagnets, RInCo_{4} ( R = Dy − Tm )},

author = {T. Shiotani and T. Waki and Y. Tabata and H. Nakamura and I. Kézsmárki},

url = {https://link.aps.org/doi/10.1103/xgkd-6jv1},

doi = {10.1103/xgkd-6jv1},

issn = {2475-9953},

year  = {2025},

date = {2025-12-17},

urldate = {2025-12-17},

journal = {Phy. Rev. Mater.},

volume = {9},

number = {12},

pages = {124411},

keywords = {A4},

pubstate = {published},

tppubtype = {article}

}

@article{zhouStatisticalSignaturesTopology2025,

title = {Statistical Signatures of Topology and Chirality in the Annihilation Field Distributions of Magnetic Thin Films},

author = {S. Zhou and K. Litzius and F. Büttner and L. Caretta},

url = {http://dx.doi.org/10.1002/adfm.202526052},

doi = {10.1002/adfm.202526052},

year  = {2025},

date = {2025-12-17},

urldate = {2025-12-01},

journal = {Adv. Funct. Mater.},

volume = {36},

number = {19},

publisher = {Wiley},

abstract = {Magnetic skyrmions are winding spin textures whose proposed stability underpins their promise for next-generation spintronic devices. While this topological stabilization is widely theorized to suppress collapse and disorder-driven annihilation, direct experimental validation has remained challenging, often requiring complex imaging techniques or indirect electrical probes. Here, a simple and general method is introduced to probe skyrmion topology statistically by analyzing annihilation field distributions in large skyrmion bubble arrays using wide-field Kerr microscopy. By systematically applying in-plane (IP) magnetic fields, the skyrmion topology is continuously tuned, enabling transitions from topologically nontrivial to trivial states. It is found that this topological transition drives a clear shift in annihilation behavior: from broad, thermally activated distributions (stochastic collapse) to narrow, sharply defined distributions (deterministic collapse), confirmed by micromagnetic simulations. This direct correlation between topological state and statistical stability provides a new route for chirality detection and skyrmion state control. This method enables accessible identification of skyrmion topology and opens new possibilities for device concepts: deterministic collapse for synchronized skyrmion deletion in memory, and topology-tunable stochasticity for probabilistic computing and random bit generation.},

keywords = {A4, C2},

pubstate = {published},

tppubtype = {article}

}

@article{zfk4-rxh1,

title = {Van Hove singularities and competing instabilities in an altermagnetic metal},

author = {P. Rao and J. Knolle and L. Classen},

url = {https://link.aps.org/doi/10.1103/zfk4-rxh1},

doi = {10.1103/zfk4-rxh1},

year  = {2025},

date = {2025-12-15},

urldate = {2025-12-15},

journal = {Phys. Rev. B},

volume = {112},

number = {23},

pages = {235140},

abstract = {Van Hove (VH) singularities in the single-particle band spectrum are important for interaction-driven quantum phases. Whereas VH points are usually spin-degenerate, in newly proposed altermagnets VH singularities can become spin-dependent, due to momentum-dependent spin polarization of the Fermi surfaces arising from combined rotation and time-reversal symmetry. We consider two altermagnetic models (𝑑𝑥2−𝑦2- and 𝑑𝑥⁢𝑦-wave) on a square lattice with spin-polarized VH points, and study their stable fixed-point solutions indicating interaction-induced instabilities using parquet renormalization group. For both models, we find new stable fixed-point solutions of the renormalization group equations which are not connected to the solution in the spin-degenerate limit. This implies that on the square lattice, the system with VH singularities is unstable with respect to altermagnetic perturbations. The leading instability for the 𝑑𝑥2−𝑦2 model is real transverse spin density wave. For the 𝑑𝑥⁢𝑦-wave model, it is found to be real transverse spin density wave at large altermagnetic splitting. At small altermagnetic splitting both imaginary charge density wave and real longitudinal spin density waves are dominant.},

note = {datadoi: 10.5281/zenodo.17868124},

keywords = {A6, B6},

pubstate = {published},

tppubtype = {article}

}

@article{song_many-body_2025,

title = {Many-body electronic structure in the pyrochlore superconductor CsBi_{2} and spin-liquid candidate Pr_{2}Ir_{2}O_{7}},

author = {W. Song and G. Liu and H. Deng and T. Yang and Y. Li and X. -Y. Yan and R. Liao and Q. Wang and J. Xu and C. Yan and Y. Zhao and H. Qin and D. Wang and W. Jing and D. Shen and K. Nakayama and T. Sato and C. Setty and D. Wu and B. Song and T. Ying and Z. Tian and A. Sakai and S. Nakatsuji and H. Kumar and C. A. Kuntscher and Z. Wang and Q. -K. Xue and J. -X. Yin},

url = {https://link.aps.org/doi/10.1103/6jq5-fgxl},

doi = {10.1103/6jq5-fgxl},

year  = {2025},

date = {2025-12-12},

urldate = {2025-12-12},

journal = {Phys. Rev. B},

volume = {112},

number = {24},

pages = {245131},

abstract = {The pyrochlore lattice materials can exhibit geometrical frustration, while the related many-body electronic states remain elusive. In this work, we performed scanning tunneling microscopy measurements on the pyrochlore superconductor Cs⁢Bi2 and spin liquid P⁢r2⁢I⁢r2⁢O7 at 0.3 K. For the first time, we obtained atomically resolved images of their (111) surfaces, revealing a hexagonal lattice or a kagome lattice. Tunneling spectroscopy in Cs⁢Bi2 reveals a nearly fully opened superconductivity gap. The ratio of 2⁢Δ/𝑘_𝐵⁢𝑇_C=4.7 suggests relatively strong coupling superconductivity, as compared with that in kagome superconductors 𝐴⁢V3⁢S⁢b5 (𝐴 = K, Rb, Cs). In contrast to the previous study categorizing Cs⁢Bi2 as a type-I superconductor, the applied magnetic field induces a hexagonal vortex lattice in which each vortex core exhibits an intriguing threefold symmetry state. In P⁢r2⁢I⁢r2⁢O7, we observed a spatially homogeneous Kondo-lattice resonance, which is compared with that in the kagome Kondo-lattice material Cs⁢Cr6⁢S⁢b6. We further discover that the Kondo resonance exhibits a spatial modulation with threefold symmetry, and the applied magnetic field induces a Zeeman splitting of the Kondo resonance with intriguing atomic site dependence. We discuss the relations of these many-body electronic phenomena with the pyrochlore lattice geometry and its charge or spin frustration. Our systematic observations offer atomic-scale insights into the many-body electronic structures of the geometrically frustrated pyrochlore superconductors and spin liquids.},

keywords = {A1},

pubstate = {published},

tppubtype = {article}

}

@article{479d-4jvy,

title = {Contrasting magnetic behavior in MnSc_{2}X_{4} (X = S, Se) spinel compounds investigated by magnetoelastic studies},

author = {J. Grumbach and J. Sourd and M. Deeb and A. Miyata and H. Suwa and T. Gottschall and A. Hauspurg and S. Chattopadhyay and M. Rotter and S. Granovsky and L. Prodan and V. Tsurkan and S. Zherlitsyn and M. Doerr and J. Wosnitza},

url = {https://link.aps.org/doi/10.1103/479d-4jvy},

doi = {10.1103/479d-4jvy},

year  = {2025},

date = {2025-12-08},

urldate = {2025-12-01},

journal = {Phys. Rev. B},

volume = {112},

number = {21},

pages = {214415},

abstract = {The spinel compounds MnSc2⁢𝑋4 are highly frustrated and candidate materials for vortex-like 3 q magnetic states, such as skyrmions, with propagation vectors in the [111] plane. Because of the strong magnetoelastic coupling, we could extract a refined magnetic (𝐻,𝑇) phase diagram for MnSc2⁢S4 from ultrasound and dilatometry measurements. We found a variety of magnetic phases, including the skyrmion phase, which is stable down to lowest temperatures. In comparison, we investigated MnSc2⁢Se4, having a larger distance between the magnetic Mn3+ ions using the same methods. Unlike in MnSc2⁢S4, we found no skyrmion phase and overall a lack of sharp anomalies indicative of phase transitions, neither in dilatometry nor ultrasound nor in specific heat and ac-susceptibility data. Motivated by our findings, we performed model calculations, which reproduced the experimentally observed magnetostriction and specific-heat results reasonably well.},

keywords = {B4},

pubstate = {published},

tppubtype = {article}

}

@article{ferrariStabilityAlgebraicSpin2025,

title = {Stability of algebraic spin liquids coupled to quantum phonons},

author = {F. Ferrari and J. Willsher and U. F. P. Seifert and R. Valentí and J. Knolle},

url = {https://link.aps.org/doi/10.1103/9wnn-w8bg},

doi = {10.1103/9wnn-w8bg},

year  = {2025},

date = {2025-12-05},

urldate = {2025-12-01},

journal = {Phys. Rev. Res.},

volume = {7},

number = {4},

pages = {L042053},

publisher = {American Physical Society},

abstract = {Algebraic spin liquids are quantum disordered phases of insulating magnets that exhibit fractionalized gapless excitations and power-law correlations. Quantum spin liquids in this category include the experimentally established one-dimensional (1D) Luttinger liquid, as well as the U(1) Dirac spin liquid (DSL) that has been a focus of recent candidate materials searches. Most notably, several exchange-frustrated Heisenberg materials on the triangular lattice have shown evidence of the U(1) DSL. In this work, we measure the algebraic correlations of spin-singlet excitations in the 𝐽1−𝐽2 antiferromagnetic Heisenberg model on the triangular lattice, prompting a detailed investigation of this model’s stability under spin-lattice coupling with dynamical quantum phonons using variational Monte Carlo. As seen before in 1D spin chains, we observe a low-temperature transition from a U(1) DSL to valence bond order and predict the parameter regime where the model realizes a stable DSL ground state. To achieve this, we employ a series of finite-size scaling Ansätze inspired by the low-energy DSL’s conformal description in terms of quantum electrodynamics and show that emergent monopole operators drive the instability. We compare the physics of this transition to the 1D Luttinger liquid throughout our analysis. We derive the regime of stability against spin-Peierls ordering and argue that the DSL ground state might still be achievable in candidate materials, despite its tendency to valence bond solid ordering.},

note = {datadoi: 10.5281/zenodo.14039384},

keywords = {B6},

pubstate = {published},

tppubtype = {article}

}

@article{misawaSuccessiveOrthorhombicDistortions2025,

title = {Successive orthorhombic distortions in kagome metals by molecular orbital formation},

author = {R. Misawa and S. Kitou and R. Yamada and T. Gaggl and R. Nakano and Y. Shibata and Y. Okamura and M. Kriener and P. R. Baral and Y. Nakamura and Y. Ōnuki and Y. Takahashi and T. Arima and M. Jovanovic and L. M. Schoop and M. Hirschberger},

url = {https://advanced.onlinelibrary.wiley.com/doi/abs/10.1002/adma.202513015},

doi = {10.1002/adma.202513015},

year  = {2025},

date = {2025-12-05},

urldate = {2025-12-01},

journal = {Adv. Mater.},

pages = {e13015},

abstract = {Abstract The kagome lattice, with its inherent frustration, hosts a plethora of exotic phenomena, including the emergence of 3q charge-density-wave order. The high rotational symmetry required to realize such an unconventional charge order is broken in many kagome materials by orthorhombic distortions at high temperature, the origin of which remains much less examined despite their ubiquity. In this study, synchrotron X-ray diffraction reveals a structural phase transition from a parent hexagonal structure to an orthorhombic groundstate, mediated by a critical regime with diffuse scattering in the prototypical kagome metals RRu3Si2 (R = Nd, Pr). Structural analysis uncovers partially ordered bonds between kagome layers in the orthorhombic phases. Accordingly, a short-range correlated dimer model on the kagome layers reproduces the diffuse scattering, with the short-range order arising from competing structures induced by the geometrical frustration of the kagome lattice. The observations point to molecular orbital formation between Ru $4d_zˆ2$ orbitals as the driving force behind the transition, consistent with ab initio calculations. A framework based on electronegativity and a tolerance factor is proposed to evaluate the stability of the hexagonal phase in various kagome metals, guiding the design of highly symmetric materials.},

keywords = {B5, C1},

pubstate = {published},

tppubtype = {article}

}

@article{romenFractionalizedPrethermalizationOnedimensional2025,

title = {Fractionalized prethermalization in the one-dimensional Hubbard model},

author = {A. Romen and J. Knolle and M. Knap},

url = {https://doi.org/10.1103/qlky-lzx6},

doi = {10.1103/qlky-lzx6},

year  = {2025},

date = {2025-11-20},

urldate = {2025-11-20},

journal = {Phys. Rev. B},

volume = {112},

number = {19},

pages = {195124},

abstract = {Prethermalization phenomena in driven systems are generally understood via a local Floquet Hamiltonian obtained from a high-frequency expansion. Remarkably, recently it has been shown that a driven Kitaev spin liquid with fractionalized excitations can realize a quasistationary state that is not captured by this paradigm. Instead distinct types of fractionalized excitations are characterized by vastly different temperatures—a phenomenon dubbed . In our work, we analyze fractionalized prethermalization in a driven one-dimensional Hubbard model at strong coupling which hosts spin-charge fractionalization. At intermediate frequencies quasisteady states emerge which are characterized by a low spin and high charge temperature with lifetimes set by two competing processes: the lifetime of the quasiparticles determined by Fermi's Golden rule and the exponentially long lifetime of a Floquet prethermal plateau. We classify drives into three categories, each giving rise to distinct (fractional) prethermalization dynamics. Resorting to a time-dependent variant of the Schrieffer-Wolff transformation, we systematically analyze how these drive categories are linked to the underlying driven Hubbard model, thereby providing a general understanding of the emergent thermalization dynamics. We discuss routes toward an experimental realization of this phenomenon in quantum simulation platforms.},

note = {datadoi: 10.5281/zenodo.17343675},

keywords = {C5, C6},

pubstate = {published},

tppubtype = {article}

}

@article{wu_alternating_2025,

title = {Alternating and Gaussian Fermionic Isometric Tensor Network States},

author = {Y. Wu and Z. Dai and S. Anand and S. -H. Lin and Q. Yang and L. Wang and F. Pollmann and M. P. Zaletel},

url = {https://link.aps.org/doi/10.1103/8ypw-c8t4},

doi = {10.1103/8ypw-c8t4},

year  = {2025},

date = {2025-11-05},

urldate = {2025-11-01},

journal = {PRX Quantum},

volume = {6},

number = {4},

pages = {040324},

abstract = {Isometric tensor networks in two dimensions enable efficient and accurate study of quantum many-body states, yet the effect of the isometric restriction on the represented quantum states is not fully understood. We address this question in two main contributions. First, we introduce an improved variant of isometric tensor network states (isoTNS) in two dimensions, where the isometric arrows on the columns of the network alternate between pointing upward and downward; hence the name alternating isometric tensor network states. Second, we introduce a numerical tool—the isometric Gaussian fermionic TNS (isoGfTNS)—that incorporates isometric constraints into the framework of Gaussian fermionic tensor network states. We demonstrate in numerous ways that alternating isoTNSs represent many-body ground states of two-dimensional quantum systems significantly better than the original isoTNSs. First, we show that the entanglement in an isoTNS is mediated along the isometric arrows and that alternating isoTNSs mediate entanglement more efficiently than conventional isoTNSs. Second, alternating isoTNSs correspond to a deeper, and thus more representative, sequential-circuit construction of depth 𝒪⁢(𝐿𝑥 ⋅𝐿𝑦) compared to the original isoTNSs of depth 𝒪⁢(𝐿𝑥 +𝐿𝑦). Third, using the Gaussian framework and gradient-based energy minimization, we provide numerical evidence of better bond-dimension scaling and variational energy of alternating isoGfTNSs for ground states of various free-fermionic models, including the Fermi surface, the band insulator, and the 𝑝𝑥 +𝑖⁢𝑝𝑦 mean-field superconductor. Finally, benchmarking on the transverse-field Ising model, we demonstrate that an alternating isoTNS provides substantially improved performance and stability relative to the original isoTNS for the ground-state search algorithm in interacting systems.},

keywords = {B6},

pubstate = {published},

tppubtype = {article}

}

@article{tsirlinKagomePBandsKagome2025,

title = {Beyond Kagome: p‐Bands in Kagome Metals},

author = {A. A. Tsirlin and E. Uykur},

url = {https://advanced.onlinelibrary.wiley.com/doi/10.1002/qute.202500336},

doi = {10.1002/qute.202500336},

issn = {2511-9044, 2511-9044},

year  = {2025},

date = {2025-11-01},

urldate = {2025-07-01},

journal = {Adv. Quantum Technol.},

volume = {8},

number = {11},

pages = {e2500336},

abstract = {Recent studies on quantum materials where transition‐metal atoms give rise to ‐bands typical of kagome metals are reviewed. Using examples from several material families – , FeGe, , and – it is argued that ‐bands contributed by elements beyond the kagome network play a crucial role in the electronic instabilities, including the charge‐density waves and superconductivity in kagome metals.},

note = {datadoi: 10.5281/zenodo.15724593},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{tangQuantumGriffithsPhase2025,

title = {Quantum Griffiths phase in the kagome Kondo lattice CeRh_{0.9}Pd_{0.1}Sn},

author = {N. Tang and R. Tripathi and Y. Shimura and T. Takabatake and D. A. Adroja and P. Gegenwart},

url = {https://link.aps.org/doi/10.1103/8lf7-j26n},

doi = {10.1103/8lf7-j26n},

issn = {2469-9950, 2469-9969},

year  = {2025},

date = {2025-10-23},

urldate = {2025-10-01},

journal = {Phys. Rev. B},

volume = {112},

number = {15},

pages = {155151},

abstract = {CeRhSn is a valence fluctuating heavy-fermion metal with a twisted Ce-kagome lattice, displaying zero-field quantum criticality, previously associated with geometrical frustration. The partial substitution of Rh by Pd in CeRh1−𝑥⁢Pd𝑥⁢Sn enlarges the unit-cell volume, suppresses valence fluctuations, decreases the Kondo temperature, and stabilizes a possible long-range antiferromagnetic (AFM) ordered ground state with 𝑇𝑁=0.8 K at 𝑥=0.5. Previous thermodynamic and spectroscopic measurements for 𝑥=0.1 suggested a quantum critical spin liquid. We report low-temperature dilatometry and magnetization measurements on CeRh0.9⁢Pd0.1⁢Sn and compare with published low-𝑇 specific heat data. The absence of a Grüneisen parameter divergence excludes a conventional quantum criticality scenario. Instead, the weak power-law divergences signal non-Fermi-liquid (NFL) behavior, according to a disorder-driven quantum Griffiths phase scenario. At low temperatures, a negative thermal expansion is found in fields above approximately 0.5 T and the NFL scaling breaks down, probably due to the polarization of AFM correlations.},

note = {datadoi: 10.5281/zenodo.16284216},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{yamadaMetallicPwaveMagnet2025,

title = {A metallic p-wave magnet with commensurate spin helix},

author = {R. Yamada and M. T. Birch and P. R. Baral and S. Okumura and R. Nakano and S. Gao and M. Ezawa and T. Nomoto and J. Masell and Y. Ishihara and K. K. Kolincio and I. Belopolski and H. Sagayama and H. Nakao and K. Ohishi and T. Ohhara and R. Kiyanagi and T. Nakajima and Y. Tokura and T. Arima and Y. Motome and M. M. Hirschmann and M. Hirschberger},

url = {https://doi.org/10.1038/s41586-025-09633-4},

doi = {10.1038/s41586-025-09633-4},

year  = {2025},

date = {2025-10-22},

urldate = {2025-10-01},

journal = {Nature},

volume = {646},

number = {8086},

pages = {837},

abstract = {Antiferromagnetic states with a spin-split electronic structure give rise to spintronic, magnonic and electronic phenomena despite (near-)zero net magnetization [1–7]. The simplest odd-parity spin splitting—p wave—was originally proposed to emerge from a collective instability in interacting electron systems [8–12]. Recent theory has identified a distinct route to realize p-wave spin-split electronic bands without strong correlations [13,14], termed p-wave magnetism. Here we demonstrate an experimental realization of a metallic p-wave magnet. The odd-parity spin splitting of delocalized conduction electrons arises from their coupling to an antiferromagnetic texture of localized magnetic moments: a coplanar spin helix whose magnetic period is an even multiple of the chemical unit cell, as revealed by X-ray scattering experiments. This texture breaks space-inversion symmetry but approximately preserves time-reversal symmetry up to a half-unit-cell translation—thereby fulfilling the symmetry conditions for p-wave magnetism. Consistent with theoretical predictions, our p-wave magnet shows a characteristic anisotropy in the electronic conductivity [13–15]. Relativistic spin–orbit coupling and a tiny spontaneous net magnetization further break time-reversal symmetry, resulting in a giant anomalous Hall effect (Hall conductivity >600 S cm−1, Hall angle >3%), for an antiferromagnet. Our model calculations show that the spin-nodal planes found in the electronic structure of p-wave magnets are readily gapped by a small perturbation to induce the anomalous Hall effect. We establish metallic p-wave magnets as an ideal platform to explore the functionality of spin-split electronic states in magnets, superconductors, and in spintronic devices.},

note = {datadoi: (10.5281/zenodo.17035625)},

keywords = {B5},

pubstate = {published},

tppubtype = {article}

}