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arXiv · 0901.0072

Quantum Goos-Hanchen effect in graphene

C. W. J. Beenakker·R. A. Sepkhanov·A. R. Akhmerov·J. Tworzydlo
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Abstract

The Goos-Hanchen (GH) effect is an interference effect on total internal reflection at an interface, resulting in a shift sigma of the reflected beam along the interface. We show that the GH effect at a p-n interface in graphene depends on the pseudospin (sublattice) degree of freedom of the massless Dirac fermions, and find a sign change of sigma at angle of incidence alpha*=arcsin[sin alpha_c]^1/2 determined by the critical angle alpha_c for total reflection. In an n-doped channel with p-doped boundaries the GH effect doubles the degeneracy of the lowest propagating mode, introducing a two-fold degeneracy on top of the usual spin and valley degeneracies. This can be observed as a stepwise increase by 8e^2/h of the conductance with increasing channel width.

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C. W. J. Beenakker, R. A. Sepkhanov, A. R. Akhmerov, J. Tworzydlo. 2009-04-10. Quantum Goos-Hanchen effect in graphene. https://doi.org/10.1103/physrevlett.102.146804

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