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arXiv · 2309.06760

Symmetry transformation of nonlinear optical current of tilted Weyl nodes and application to ferromagnetic MnBi2Te4

Zhuocheng Lu·Ji Feng
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Abstract

A Weyl node is characterized by its chirality and tilt. We develop a theory of how $n$th-order nonlinear optical conductivity behaves under transformations of anisotropic tensor and tilt, which clarify how chirality-dependent and -independent parts of optical conductivity transform under the reversal of tilt and chirality. Built on this theory, we propose ferromagnetic $\rm MnBi_{2}Te_{4}$ as a magnetoelectrically regulated, terahertz optical device, by magnetoelectrically switching the chirality-dependent and -independent dc photocurrents. These results are useful for creating nonlinear optical devices based on topological Weyl semimetals.

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Zhuocheng Lu, Ji Feng. 2023-09-13. Symmetry transformation of nonlinear optical current of tilted Weyl nodes and application to ferromagnetic MnBi2Te4. https://arxiv.org/abs/2309.06760

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