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arXiv · 2205.06616

High-order harmonic generations in tilted Weyl semimetals

Zi-Yuan Li·Qi Li·Zhou Li
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Abstract

We investigate high-order harmonic generations (HHGs) under the comparison of Weyl cones in two types. Due to the hyperboloidal electron pocket structure, strong noncentrosymmetrical generations in high orders are observed around a single type-II Weyl point, especially at frequency zero. Such remarkable DC signal is proved to have attributions from the intraband transition after spectral decomposition. Under weak pulse electric field , the linear optical response of a non-tilted Weyl cone is consistent with the Kubo theory. With more numerical simulations, we conclude the non-zero chemical potential can enhance the even-order generations, from the slightly tilted system to the over-tilted systems. In consideration of dynamical symmetries, type-I and -II Weyl cones also show different selective responses under the circularly polarized light. Finally, using a more realistic model containing two pairs of Weyl points, we demonstrate the paired Weyl points with opposite chirality could suppress the overall even-order generations.

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Zi-Yuan Li, Qi Li, Zhou Li. 2022-05-11. High-order harmonic generations in tilted Weyl semimetals. https://doi.org/10.1088/1674-1056%2Fac9220

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