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Tails of Localized Density of States of Two-dimensional Dirac Fermions

Simon Villain-Guillot·Giancarlo Jug·Klaus Ziegler
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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.

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Simon Villain-Guillot, Giancarlo Jug, Klaus Ziegler. 1999-08-23. Tails of Localized Density of States of Two-dimensional Dirac Fermions. https://doi.org/10.1002/(sici)1521-3889(200001)9%3A1%3C27%3A%3Aaid-andp27%3E3.0.co%3B2-i

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