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arXiv · 1708.08040

Fermionic symmetry-protected topological state in strained graphene

Ying-Hai Wu·Tao Shi·G. J. Sreejith·Zheng-Xin Liu
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Abstract

The low-energy physics of graphene is described by relativistic Dirac fermions with spin and valley degrees of freedom. Mechanical strain can be used to create a pseudo magnetic field pointing to opposite directions in the two valleys. We study interacting electrons in graphene exposed to both an external real magnetic field and a strain-induced pseudo magnetic field. For a certain ratio between these two fields, it is proposed that a fermionic symmetry-protected topological state can be realized. The state is characterized in detail using model wave functions, Chern-Simons field theory, and numerical calculations. Our paper suggests that graphene with artificial gauge fields may host a rich set of topological states.

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Ying-Hai Wu, Tao Shi, G. J. Sreejith, Zheng-Xin Liu. 2017-08-27. Fermionic symmetry-protected topological state in strained graphene. https://doi.org/10.1103/physrevb.96.085138

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