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arXiv · 2211.11231

Giant Magnetochiral Anisotropy in Weyl-semimetal WTe2 Induced by Diverging Berry Curvature

Tomoyuki Yokouchi·Yuya Ikeda·Takahiro Morimoto·Yuki Shiomi
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Abstract

The concept of Berry curvature is essential for various transport phenomena. However, an effect of the Berry curvature on magnetochiral anisotropy, i.e. nonreciprocal magneto-transport, is still elusive. Here, we report the Berry curvature originates the large magnetochiral anisotropy. In Weyl-semimetal WTe2, we observed the strong enhancement of the magnetochiral anisotropy when the Fermi level is located near the Weyl points. Notably, the maximal figure of merit $\bar{\gamma}$ reaches $1.2\,{\times}10^{-6} \rm{m^2T^{-1}A^{-1}}$, which is the largest ever reported in bulk materials. Our semiclassical calculation shows that the diverging Berry curvature at the Weyl points strongly enhances the magnetochiral anisotropy.

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Tomoyuki Yokouchi, Yuya Ikeda, Takahiro Morimoto, Yuki Shiomi. 2022-11-21. Giant Magnetochiral Anisotropy in Weyl-semimetal WTe2 Induced by Diverging Berry Curvature. https://doi.org/10.1103/physrevlett.130.136301

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