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arXiv · 1912.07732

Topological magnetotorsional effect in Weyl semimetals

Long Liang·Teemu Ojanen
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Abstract

In this work we introduce a thermal magnetotorsional effect (TME) as a novel topological response in magnetic Weyl semimetals. We predict that magnetization gradients perpendicular to the Weyl node separation give rise to temperature gradients depending only on the local positions of the Weyl nodes. The TME is a consequence of magnetization-induced effective torsional spacetime geometry and the finite temperature Nieh-Yan anomaly. Similarly to anomalous Hall effect and chiral anomaly, the TME has a universal material-independent form. We predict that the TME can be observed in magnetic Weyl semimetal EuCd$_2$As$_2$.

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Long Liang, Teemu Ojanen. 2019-12-16. Topological magnetotorsional effect in Weyl semimetals. https://doi.org/10.1103/physrevresearch.2.022016

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