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arXiv · 2007.08372

Deformation of graphene sheet: Interaction of fermions with phonons

Ara Sedrakyan·Andreas Sinner·Klaus Ziegler
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Abstract

We construct an effective low energy Hamiltonian which describes fermions dwelling on a deformed honeycomb lattice with dislocations and disclinations, and with an arbitrary hopping parameters of the corresponding tight binding model. It describes the interaction of fermions with a 2d gravity and has also a local SU(2) gauge invariance of the group of rotations. We reformulate the model as interaction of fermions with the deformation of the lattice, which forms a phonon field. We calculate the response of fermion currents to the external deformation or phonon field, which is a result of a Z_2 anomaly. This can be detected experimentally.

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Ara Sedrakyan, Andreas Sinner, Klaus Ziegler. 2020-07-16. Deformation of graphene sheet: Interaction of fermions with phonons. https://doi.org/10.1103/physrevb.103.l201104

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