Gippius, A. A.; Zhurenko, S. V.; Tkachev, A. V.; Gunbin, A. V.; Büttgen, N.; Schaedler, M.; Silkin, I. G.; Morozov, I. V.; Bogach, A. V.; Sobolev, A. V.; Presniakov, I. A.; Moskvin, A. S. Short-range helical magnetic order in FeP1-xAsx (x = 0.33 and 0.5) Journal Article J. Magn. Magn. Mater. 651, 174177 (2026). @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 = {},
pubstate = {published},
tppubtype = {article}
}
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. |
Chmeruk, A.; Jones, D.; Dwadasi, R.; Ebad-Allah, J.; Beiuşeanu, F.; Schilberth, F.; Kassem, M. A.; Schade, U.; Veber, A.; Puskar, L.; Tabata, Y.; Waki, T.; Nakamura, H.; Kuntscher, C. A.; Östlin, A.; Chioncel, L. Suppression of magnetism in Co3Sn2S2 under external pressure Journal Article Phys. Rev. B 114, 024423 (2026). @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 Co3Sn2S2 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 = {},
pubstate = {published},
tppubtype = {article}
}
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 Co3Sn2S2 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. |
Lamp, M.; Ebad-Allah, J.; Chmeruk, A.; Bura, N.; Schönemann, R.; Balicas, L.; Lee, S. H.; Mao, Z. Q.; Chioncel, L.; Kuntscher, C. A. Charge dynamics in the Weyl semimetals NbIrTe4 and TaIrTe4 under pressure: Signatures of an electronic phase transition Journal Article Phys. Rev. B 114, 065101 (2026). @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.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
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. |
