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arXiv · 1909.04459

Crystal Structures and Phase Transitions of the van-der-Waals Ferromagnet VI3

Petr Doležal·Marie Kratochvílová·Václav Holý·Petr Čermák·Vladimír Sechovský·Michal Dušek·Martin Míšek·Tirthankar Chakraborty·Yukio Noda·Suhan Son·Je-Geun Park
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Abstract

The results of a single-crystal X-ray-diffraction study of the evolution of crystal structures of VI3 with temperature with emphasis on phase transitions are presented. Some related specific-heat and magnetization data are included. The existence of the room-temperature trigonal crystal structure R-3 (148) has been confirmed. Upon cooling, VI3 undergoes a structural phase transition to a monoclinic phase at Ts ~ 79 K. Ts is reduced in magnetic fields applied along the trigonal c-axis. When VI3 becomes ferromagnetic at TFM1 ~ 50 K, magnetostriction-induced changes of the monoclinic-structure parameters are observed. Upon further cooling, the monoclinic structure transforms into a triclinic variant at 32 K which is most likely occurring in conjunction with the previously reported transformation of the ferromagnetic structure. The observed phenomena are preliminarily attributed to strong magnetoelastic interactions.

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Petr Doležal, Marie Kratochvílová, Václav Holý, Petr Čermák, Vladimír Sechovský, Michal Dušek, Martin Míšek, Tirthankar Chakraborty, Yukio Noda, Suhan Son, Je-Geun Park. 2019-09-10. Crystal Structures and Phase Transitions of the van-der-Waals Ferromagnet VI3. https://doi.org/10.1103/physrevmaterials.3.121401

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