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arXiv · 1801.08277

Dielectric Evidence for Possible Type-II Multiferroicity in alpha-RuCl3

Jia-Cheng Zheng·Yi Cui·Tian-Run Li·Ke-Jing Ran·Jinsheng Wen·Weiqiang Yu
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Abstract

$\alpha$-RuCl$_3$ is a Mott insulator with a honeycomb lattice with strong spin-orbit coupling. We report dielectric measurements on $\alpha$-RuCl$_3$ single crystals under field. At zero field, the dielectric constant, $\epsilon$, drops rapidly when cooled through the magnetic transition temperature T$_N$. With increasing field, the onset of the drop in $\epsilon$ tracks the T$_N$. Such behavior is absent with field above a critical value H$_c$ ~ 7.5 T, indicating the onset of a quantum phase transition. Our data suggest that the dielectric constant can be used as a probe of magnetic ordering in $\alpha$-RuCl$_3$, and $\alpha$-RuCl$_3$ is a possible type-II multiferroics.

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Jia-Cheng Zheng, Yi Cui, Tian-Run Li, Ke-Jing Ran, Jinsheng Wen, Weiqiang Yu. 2018-01-25. Dielectric Evidence for Possible Type-II Multiferroicity in alpha-RuCl3. https://doi.org/10.1007/s11433-017-9166-1

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