Tails of Localized Density of States of Two-dimensional Dirac Fermions
arXiv:cond-mat/9908318 · doi:10.1002/(SICI)1521-3889(200001)9:1<27::AID-ANDP27>3.0.CO;2-I
Abstract
The density of states of Dirac fermions with a random mass on a two-dimensional lattice is considered. We give the explicit asymptotic form of the single-electron density of states as a function of both energy and (average) Dirac mass, in the regime where all states are localized. We make use of a weak-disorder expansion in the parameter g/m^2, where g is the strength of disorder and m the average Dirac mass for the case in which the evaluation of the (supersymmetric) integrals corresponds to non-uniform solutions of the saddle point equation. The resulting density of states has tails which deviate from the typical pure Gaussian form by an analytic prefactor.
arXiv comment8 pages, REVTeX, 1 eps figure; to appear in Annalen der Physik