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arXiv · 1008.4858

Valley-dependent Brewster angles and Goos-Hanchen effect in strained graphene

Zhenhua Wu·F. Zhai·F. M. Peeters·H. Q. Xu·Kai Chang
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Abstract

We demonstrate theoretically how local strains in graphene can be tailored to generate a valley polarized current. By suitable engineering of local strain profiles, we find that electrons in opposite valleys (K or K') show different Brewster-like angles and Goos-Hänchen shifts, exhibiting a close analogy with light propagating behavior. In a strain-induced waveguide, electrons in K and K' valleys have different group velocities, which can be used to construct a valley filter in graphene without the need for any external fields.

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Zhenhua Wu, F. Zhai, F. M. Peeters, H. Q. Xu, Kai Chang. 2011-09-26. Valley-dependent Brewster angles and Goos-Hanchen effect in strained graphene. https://doi.org/10.1103/physrevlett.106.176802

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