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arXiv · 1203.4368

Resonant modes in strain-induced graphene superlattices

F. M. D. Pellegrino·G. G. N. Angilella·R. Pucci
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Abstract

We study tunneling across a strain-induced superlattice in graphene. In studying the effect of applied strain on the low-lying Dirac-like spectrum, both a shift of the Dirac points in reciprocal space, and a deformation of the Dirac cones is explicitly considered. The latter corresponds to an anisotropic, possibly non-uniform, Fermi velocity. Along with the modes with unit transmission usually found across a single barrier, we analytically find additional resonant modes when considering a periodic structure of several strain-induced barriers. We also study the band-like spectrum of bound states, as a function of conserved energy and transverse momentum. Such a strain-induced superlattice may thus effectively work as a mode filter for transport in graphene.

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F. M. D. Pellegrino, G. G. N. Angilella, R. Pucci. 2012-03-20. Resonant modes in strain-induced graphene superlattices. https://doi.org/10.1103/physrevb.85.195409

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