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arXiv · 1308.1595

Generalized effective hamiltonian for graphene under non-uniform strain

Juan L. Mañes·Fernando de Juan·Mauricio Sturla·María A. H. Vozmediano
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Abstract

We use a symmetry approach to construct a systematic derivative expansion of the low energy effective Hamiltonian modifying the continuum Dirac description of graphene in the presence of non-uniform elastic deformations. We extract all experimentally relevant terms and describe their physical significance. Among them there is a new gap-opening term that describes the Zeeman coupling of the elastic pseudomagnetic field and the pseudospin. We determine the value of the couplings using a generalized tight binding model.

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Juan L. Mañes, Fernando de Juan, Mauricio Sturla, María A. H. Vozmediano. 2015-05-24. Generalized effective hamiltonian for graphene under non-uniform strain. https://doi.org/10.1103/physrevb.88.155405

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