Probing of valley polarization in graphene via optical second-harmonic generation

T. O. Wehling; A. Huber; A. I. Lichtenstein; M. I. Katsnelson

doi:10.1103/physrevb.91.041404

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arXiv · 1407.6808

Probing of valley polarization in graphene via optical second-harmonic generation

T. O. Wehling·A. Huber·A. I. Lichtenstein·M. I. Katsnelson

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Abstract

Valley polarization in graphene breaks inversion symmetry and therefore leads to second-harmonic generation. We present a complete theory of this effect within a single-particle approximation. It is shown that this may be a sensitive tool to measure the valley polarization created, e.g., by polarized light and, thus, can be used for a development of ultrafast valleytronics in graphene.

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T. O. Wehling, A. Huber, A. I. Lichtenstein, M. I. Katsnelson. 2014-07-25. Probing of valley polarization in graphene via optical second-harmonic generation. https://doi.org/10.1103/physrevb.91.041404

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