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arXiv · 1701.02715

Lattice symmetries, spectral topology and opto-electronic properties of graphene-like materials

K. Ziegler·A. Sinner
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Abstract

The topology of the band structure, which is determined by the lattice symmetries, has a strong influence on the transport properties. Here we consider an anisotropic honeycomb lattice and study the effect of a continuously deformed band structure on the optical conductivity and on diffusion due to quantum fluctuations. In contrast to the behavior at an isotropic node we find super- and subdiffusion for the anisotropic node. The spectral saddle points create van Hove singularities in the optical conductivity, which could be used to characterize the spectral properties experimentally.

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K. Ziegler, A. Sinner. 2017-01-10. Lattice symmetries, spectral topology and opto-electronic properties of graphene-like materials. https://doi.org/10.1209/0295-5075%2F119%2F27001

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