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arXiv · 1806.00639

Pressure-induced enhancement of non-polar to polar transition temperature in metallic LiOsO$_3$

Esteban I. Paredes Aulestia·Yiu Wing Cheung·Yue-Wen Fang·Jianfeng He·Kazunari Yamaura·Kwing To Lai·Swee K. Goh·Hanghui Chen
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Abstract

LiOsO$_3$ undergoes a continuous transition from a centrosymmetric $R\bar{3}c$ structure to a polar $R3c$ structure at $T_s=140$~K. By combining transport measurements and first-principles calculations, we find that $T_s$ is enhanced by applied pressure, and it reaches a value of $\sim$250~K at $\sim$6.5~GPa. The enhancement is due to the fact that the polar $R3c$ structure of LiOsO$_3$ has a smaller volume than the centrosymmetric $R\bar{3}c$ structure. Pressure generically favors the structure with the smallest volume, and therefore further stabilizes the polar $R3c$ structure over the $R\bar{3}c$ structure, leading to the increase in $T_s$.

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Esteban I. Paredes Aulestia, Yiu Wing Cheung, Yue-Wen Fang, Jianfeng He, Kazunari Yamaura, Kwing To Lai, Swee K. Goh, Hanghui Chen. 2018-06-06. Pressure-induced enhancement of non-polar to polar transition temperature in metallic LiOsO$_3$. https://doi.org/10.1063/1.5035133

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