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arXiv · 0806.4884

Quantum chaos in disordered graphene

Abstract

We have studied numerically the statistics for electronic states (level-spacings and participation ratios) from disordered graphene of finite size, described by the aspect ratio $W/L$ and various geometries, including finite or torroidal, chiral or achiral carbon nanotubes. Quantum chaotic Wigner energy level-spacing distribution is found for weak disorder, even infinitesimally small disorder for wide and short samples ($W/L>>1$), while for strong disorder Anderson localization with Poisson level-statistics always sets in. Although pure graphene near the Dirac point corresponds to integrable ballistic statistics chaotic diffusive behavior is more common for realistic samples.

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BibTeXRIS

I. Amanatidis, S. N. Evangelou. 2008-06-30. Quantum chaos in disordered graphene. https://doi.org/10.1103/physrevb.79.205420

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