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arXiv · 1410.3411

Topological properties of the bond-modulated honeycomb lattice

F. Grandi·F. Manghi·O. Corradini·C. M. Bertoni
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Abstract

We study the combined effects of lattice deformation, e-e interaction and spin-orbit coupling in a two-dimensional (2D) honeycomb lattice. We adopt different kinds of hopping modulation--generalized dimerization and a Kekule distortion--and calculate topological invariants for the non-interacting system and for the interacting system. We identify the parameter range (Hubbard U, hopping modulation, spin-orbit coupling) where the 2D system behaves as a trivial insulator or Quantum Spin Hall Insulator.

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F. Grandi, F. Manghi, O. Corradini, C. M. Bertoni. 2015-03-06. Topological properties of the bond-modulated honeycomb lattice. https://doi.org/10.1103/physrevb.91.115112

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