%0 Journal Article %1 PhysRevB.106.134432 %A Wolf, B. %A Kaib, D. A. S. %A Razpopov, A. %A Biswas, S. %A Riedl, K. %A Winter, S. M. %A Valentí, R. %A Saito, Y. %A Hartmann, S. %A Vinokurova, E. %A Doert, T. %A Isaeva, A. %A Bastien, G. %A Wolter, A. U. B. %A Büchner, B. %A Lang, M. %D 2022 %I American Physical Society %J Phys. Rev. B %K b %N 13 %P 134432 %R 10.1103/PhysRevB.106.134432 %T Combined experimental and theoretical study of hydrostatic He-gas pressure effects in α-RuCl$_3$ %U https://link.aps.org/doi/10.1103/PhysRevB.106.134432 %V 106 %X We report a detailed experimental and theoretical study on the effect of hydrostatic pressure on various structural and magnetic aspects of the layered honeycomb antiferromagent α-RuCl3. Through measurements of the magnetic susceptibility χ performed under almost ideal hydrostatic-pressure conditions by using helium as a pressure-transmitting medium, we find that the phase transition to zigzag-type antiferromagnetic order at TN = 7.3 K can be rapidly suppressed to about 6.1 K at a weak pressure of about 94 MPa. A further suppression of TN with increasing pressure is impeded, however, due to the occurrence of a pressure-induced structural transition at p 104 MPa, accompanied by a strong dimerization of Ru-Ru bonds, which gives rise to a collapse of the magnetic susceptibility. Whereas the dimerization transition is strongly first order, the magnetic transition under varying pressure and magnetic field also reveals indications for a weakly first-order transition. We assign this observation to a strong magnetoelastic coupling in this system. Measurements of χ under varying pressure in the paramagnetic regime (T > TN ) and before dimerization (p < 100 MPa) reveal a considerable increase of χ with pressure. These experimental observations are consistent with the results of ab initio density functional theory (DFT) calculations on the pressure-dependent structure of α-RuCl3 and the corresponding pressure-dependent magnetic model. We find that pressure strengthens the nearest-neighbor Heisenberg J and off-diagonal anisotropic Γ coupling and simultaneously weakens the Kitaev K and anisotropic Γ′ coupling. Comparative susceptibility measurements on a second crystal showing two consecutive magnetic transitions instead of one, indicating the influence of stacking faults, reveal that by the application of different temperature-pressure protocols the effect of these stacking faults can be temporarily overcome

@article{PhysRevB.106.134432, abstract = {We report a detailed experimental and theoretical study on the effect of hydrostatic pressure on various structural and magnetic aspects of the layered honeycomb antiferromagent α-RuCl3. Through measurements of the magnetic susceptibility χ performed under almost ideal hydrostatic-pressure conditions by using helium as a pressure-transmitting medium, we find that the phase transition to zigzag-type antiferromagnetic order at TN = 7.3 K can be rapidly suppressed to about 6.1 K at a weak pressure of about 94 MPa. A further suppression of TN with increasing pressure is impeded, however, due to the occurrence of a pressure-induced structural transition at p 104 MPa, accompanied by a strong dimerization of Ru-Ru bonds, which gives rise to a collapse of the magnetic susceptibility. Whereas the dimerization transition is strongly first order, the magnetic transition under varying pressure and magnetic field also reveals indications for a weakly first-order transition. We assign this observation to a strong magnetoelastic coupling in this system. Measurements of χ under varying pressure in the paramagnetic regime (T > TN ) and before dimerization (p < 100 MPa) reveal a considerable increase of χ with pressure. These experimental observations are consistent with the results of ab initio density functional theory (DFT) calculations on the pressure-dependent structure of α-RuCl3 and the corresponding pressure-dependent magnetic model. We find that pressure strengthens the nearest-neighbor Heisenberg J and off-diagonal anisotropic Γ coupling and simultaneously weakens the Kitaev K and anisotropic Γ′ coupling. Comparative susceptibility measurements on a second crystal showing two consecutive magnetic transitions instead of one, indicating the influence of stacking faults, reveal that by the application of different temperature-pressure protocols the effect of these stacking faults can be temporarily overcome}, added-at = {2023-05-17T13:43:19.000+0200}, author = {Wolf, B. and Kaib, D. A. S. and Razpopov, A. and Biswas, S. and Riedl, K. and Winter, S. M. and Valentí, R. and Saito, Y. and Hartmann, S. and Vinokurova, E. and Doert, T. and Isaeva, A. and Bastien, G. and Wolter, A. U. B. and Büchner, B. and Lang, M.}, biburl = {https://www.bibsonomy.org/bibtex/2cc348e726d15525301071abbea706c58/ctqmat}, day = 26, description = {Combined experimental and theoretical study of hydrostatic He-gas pressure effects in α-RuCl3}, doi = {10.1103/PhysRevB.106.134432}, interhash = {4b623591bb03aeb3ce3d415d26487774}, intrahash = {cc348e726d15525301071abbea706c58}, journal = {Phys. Rev. B}, keywords = {b}, month = {10}, number = 13, numpages = {13}, pages = 134432, publisher = {American Physical Society}, timestamp = {2023-10-18T13:28:12.000+0200}, title = {Combined experimental and theoretical study of hydrostatic He-gas pressure effects in α-RuCl$_{\mathbf{3}}$}, url = {https://link.aps.org/doi/10.1103/PhysRevB.106.134432}, volume = 106, year = 2022 }