Hua, N.; Breitner, F.; Jesche, A.; Huang, S. -W.; Rüegg, C.; Gegenwart, P. Structural and magnetic properties of β-Li2IrO3 after grazing-angle focused ion beam thinning Journal Article Acta Crystallogr. B 81, 202 (2025). @article{hua_structural_2025,
title = {Structural and magnetic properties of β-Li_{2}IrO_{3} after grazing-angle focused ion beam thinning},
author = {N. Hua and F. Breitner and A. Jesche and S. -W. Huang and C. Rüegg and P. Gegenwart},
url = {https://doi.org/10.1107/S2052520625000587},
doi = {10.1107/S2052520625000587},
year = {2025},
date = {2025-04-01},
urldate = {2025-04-01},
journal = {Acta Crystallogr. B},
volume = {81},
number = {2},
pages = {202},
abstract = {Manipulating the size and orientation of quantum materials is often used to tune emergent phenomena, but precise control of these parameters is also necessary from an experimental point of view. Various synthesis techniques already exist, such as epitaxial thin film growth and chemical etching, that are capable of producing specific sample dimensions with high precision. However, certain materials exist as single crystals that are often difficult to manipulate, thereby limiting their studies to a certain subset of experimental techniques. One particular class of these materials includes lithium and sodium iridates, which are promising candidates for hosting a Kitaev quantum spin liquid state. Here a controlled method of using a focused ion beam at grazing incidence to reduce the size of a β-Li_2IrO_3 single crystal to a thickness of 1–2𝜇m is presented. Subsequent X-ray diffraction measurements show the lattice remains intact, albeit with a larger mosaic spread. The integrity of the magnetic order is also preserved as the temperature dependent magnetic diffraction peak follows the same trend as its bulk counterpart with a transition temperature at textitT = 37.5K. Our study demonstrates a technique that opens up the possibility of nonequilibrium experiments where submicron thin samples are often essential.},
keywords = {B1},
pubstate = {published},
tppubtype = {article}
}
Manipulating the size and orientation of quantum materials is often used to tune emergent phenomena, but precise control of these parameters is also necessary from an experimental point of view. Various synthesis techniques already exist, such as epitaxial thin film growth and chemical etching, that are capable of producing specific sample dimensions with high precision. However, certain materials exist as single crystals that are often difficult to manipulate, thereby limiting their studies to a certain subset of experimental techniques. One particular class of these materials includes lithium and sodium iridates, which are promising candidates for hosting a Kitaev quantum spin liquid state. Here a controlled method of using a focused ion beam at grazing incidence to reduce the size of a β-Li_2IrO_3 single crystal to a thickness of 1–2𝜇m is presented. Subsequent X-ray diffraction measurements show the lattice remains intact, albeit with a larger mosaic spread. The integrity of the magnetic order is also preserved as the temperature dependent magnetic diffraction peak follows the same trend as its bulk counterpart with a transition temperature at textitT = 37.5K. Our study demonstrates a technique that opens up the possibility of nonequilibrium experiments where submicron thin samples are often essential. |
Halloran, T.; Wang, Y.; Plumb, K. W.; Stone, M. B.; Winn, B.; Graves-Brook, M. K.; Rodriguez-Rivera, J. A.; Qui, Y.; Chauhan, P.; Knolle, J.; Moessner, R.; Armitage, N. P.; Takayama, T.; Takagi, H.; Broholm, C. Continuum of magnetic excitations in the Kitaev honeycomb iridate D3LiIr2O6 Journal Article npj Quantum Mater. 10, 35 (2025). @article{halloran_continuum_2025,
title = {Continuum of magnetic excitations in the Kitaev honeycomb iridate D_{3}LiIr_{2}O_{6}},
author = {T. Halloran and Y. Wang and K. W. Plumb and M. B. Stone and B. Winn and M. K. Graves-Brook and J. A. Rodriguez-Rivera and Y. Qui and P. Chauhan and J. Knolle and R. Moessner and N. P. Armitage and T. Takayama and H. Takagi and C. Broholm},
url = {https://www.nature.com/articles/s41535-025-00748-5},
doi = {10.1038/s41535-025-00748-5},
year = {2025},
date = {2025-03-29},
urldate = {2025-03-29},
journal = {npj Quantum Mater.},
volume = {10},
pages = {35},
abstract = {Inelastic neutron scattering (INS) measurements of powder D3LiIr2O6 reveal low energy magnetic excitations with a scattering cross-section that is broad in ∣Q∣ and energy transfer. The magnetic nature of the excitation spectrum is demonstrated by longitudinally polarized neutron scattering. The total magnetic moment of 1.8(4)μB/Ir inferred from the observed magnetic scattering cross-section is consistent with the effective moment inferred from magnetic susceptibility data and expectations for the Jeff = 1/2 single ion state. The rise in the dynamic correlation function S(Q, ω) for ℏω < 5 meV can be described by a simple model assuming nearest-neighbor anisotropic spin exchange, such as that found in the Kitaev model. Exchange disorder associated with the D site likely plays an important role in stabilizing the low T quantum fluctuating state.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Inelastic neutron scattering (INS) measurements of powder D3LiIr2O6 reveal low energy magnetic excitations with a scattering cross-section that is broad in ∣Q∣ and energy transfer. The magnetic nature of the excitation spectrum is demonstrated by longitudinally polarized neutron scattering. The total magnetic moment of 1.8(4)μB/Ir inferred from the observed magnetic scattering cross-section is consistent with the effective moment inferred from magnetic susceptibility data and expectations for the Jeff = 1/2 single ion state. The rise in the dynamic correlation function S(Q, ω) for ℏω < 5 meV can be described by a simple model assuming nearest-neighbor anisotropic spin exchange, such as that found in the Kitaev model. Exchange disorder associated with the D site likely plays an important role in stabilizing the low T quantum fluctuating state. |
Que, X.; He, Q.; Zhou, L.; Lei, S.; Schoop, L.; Huang, D.; Takagi, H. Visualizing the internal structure of the charge-density-wave state in CeSbTe Journal Article Nat. Commun. 16, 3053 (2025). @article{que_visualizing_2025,
title = {Visualizing the internal structure of the charge-density-wave state in CeSbTe},
author = {X. Que and Q. He and L. Zhou and S. Lei and L. Schoop and D. Huang and H. Takagi},
url = {https://doi.org/10.1038/s41467-025-58417-x},
doi = {10.1038/s41467-025-58417-x},
year = {2025},
date = {2025-03-28},
urldate = {2025-03-01},
journal = {Nat. Commun.},
volume = {16},
number = {1},
pages = {3053},
abstract = {The collective reorganization of electrons into a charge density wave has long served as a textbook example of an ordered phase in condensed matter physics. Two-dimensional square lattices with p electrons are well-suited to the realization of charge density waves, due to the anisotropy of the p orbitals and the resulting one dimensionality of the electronic structure. In spite of a long history of study of charge density waves in square-lattice systems, few reports have recognized the significance of a hidden orbital degree of freedom. The degeneracy of px and py electrons may give rise to orbital patterns in real space that endow the charge density wave with additional broken symmetries or unusual order parameters. Here, we use scanning tunneling microscopy to visualize the internal structure of the charge-density-wave state of CeSbTe, which contains Sb square lattices with 5p electrons. We image atomic-sized, anisotropic lobes of charge density with periodically modulating anisotropy, which we interpret in terms of a superposition of px and py bond density waves. Our results support the fact that delocalized p orbitals can reorganize into emergent electronic states of matter.},
keywords = {A3},
pubstate = {published},
tppubtype = {article}
}
The collective reorganization of electrons into a charge density wave has long served as a textbook example of an ordered phase in condensed matter physics. Two-dimensional square lattices with p electrons are well-suited to the realization of charge density waves, due to the anisotropy of the p orbitals and the resulting one dimensionality of the electronic structure. In spite of a long history of study of charge density waves in square-lattice systems, few reports have recognized the significance of a hidden orbital degree of freedom. The degeneracy of px and py electrons may give rise to orbital patterns in real space that endow the charge density wave with additional broken symmetries or unusual order parameters. Here, we use scanning tunneling microscopy to visualize the internal structure of the charge-density-wave state of CeSbTe, which contains Sb square lattices with 5p electrons. We image atomic-sized, anisotropic lobes of charge density with periodically modulating anisotropy, which we interpret in terms of a superposition of px and py bond density waves. Our results support the fact that delocalized p orbitals can reorganize into emergent electronic states of matter. |
