Topological delocalization of two-dimensional massless Dirac fermions

Nomura, Kentaro; Koshino, Mikito; Ryu, Shinsei

Topological delocalization of two-dimensional massless Dirac fermions

Authors

Nomura, Kentaro

Koshino, Mikito

Ryu, Shinsei

Description

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.
4 pages, 2 figures