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arXiv · 0705.1607

Topological delocalization of two-dimensional massless Dirac fermions

Kentaro Nomura·Mikito Koshino·Shinsei Ryu
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Abstract

The beta function of a two-dimensional massless Dirac Hamiltonian subject to a random scalar potential, which e.g., underlies the theoretical description of graphene, is computed numerically. Although it belongs to, from a symmetry standpoint, the two-dimensional symplectic class, the beta function monotonically increases with decreasing $g$. We also provide an argument based on the spectral flows under twisting boundary conditions, which shows that none of states of the massless Dirac Hamiltonian can be localized.

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Kentaro Nomura, Mikito Koshino, Shinsei Ryu. 2007-08-17. Topological delocalization of two-dimensional massless Dirac fermions. https://doi.org/10.1103/physrevlett.99.146806

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