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arXiv · 0811.4396

A tight-binding approach to uniaxial strain in graphene

Vitor M. Pereira·A. H. Castro Neto·N. M. R. Peres
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Abstract

We analyze the effect of tensional strain in the electronic structure of graphene. In the absence of electron-electron interactions, within linear elasticity theory, and a tight-binding approach, we observe that strain can generate a bulk spectral gap. However this gap is critical, requiring threshold deformations in excess of 20%, and only along preferred directions with respect to the underlying lattice. The gapless Dirac spectrum is robust for small and moderate deformations, and the gap appears as a consequence of the merging of the two inequivalent Dirac points, only under considerable deformations of the lattice. We discuss how strain-induced anisotropy and local deformations can be used as a means to affect transport characteristics and pinch off current flow in graphene devices.

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Vitor M. Pereira, A. H. Castro Neto, N. M. R. Peres. 2009-07-15. A tight-binding approach to uniaxial strain in graphene. https://doi.org/10.1103/physrevb.80.045401

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