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arXiv · 2106.01600

Nonlinear circular valley photogalvanic effect

M. V. Entin·V. M. Kovalev
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Abstract

We develop a theory of circular photogalvanic effect in non-gyrotropic two-dimensional transition metal dichalcogenide monolayers under interband optical transitions. Oblique incidence of circularly-polarized electromagnetic field or normal incidence of elliptically polarized electromagnetic field is assumed. In contrast to the linear-in-intensity conventional photogalvanic effect, the effect considered here arises in the second intensity order. The effect is conditioned by i) the predominant population of the valleys by the circular in-plane electromagnetic field component and ii) the direct drift of the photo-excited carriers by the linear-polarized in-plane electromagnetic field component in the presence of trigonal valley asymmetry.

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M. V. Entin, V. M. Kovalev. 2021-06-03. Nonlinear circular valley photogalvanic effect. https://doi.org/10.1103/physrevb.104.075424

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