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

摘要

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