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arXiv · 0802.3565

Berry Curvature in Graphene: A New Approach

Pierre Gosselin·Alain Bérard·Hervé Mohrbach·Subir Ghosh
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Abstract

In the present paper we have directly computed the Berry curvature terms relevant for Graphene in the presence of an \textit{inhomogeneous} lattice distortion. We have employed the generalized Foldy Wouthuysen framework, developed by some of us \cite{ber0,ber1,ber2}. We show that a non-constant lattice distortion leads to a valley-orbit coupling which is responsible to a valley-Hall effect. This is similar to the valley-Hall effect induced by an electric field proposed in \cite{niu2} and is the analogue of the spin-Hall effect in semiconductors \cite{MURAKAMI, SINOVA}. Our general expressions for Berry curvature, for the special case of homogeneous distortion, reduce to the previously obtained results \cite{niu2}. We also discuss the Berry phase in the quantization of cyclotron motion.

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Pierre Gosselin, Alain Bérard, Hervé Mohrbach, Subir Ghosh. 2008-11-24. Berry Curvature in Graphene: A New Approach. https://doi.org/10.1140/epjc%2Fs10052-008-0839-4

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