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arXiv:cond-mat/9804133 · Physical Review Letters

Exact Multifractality for Disordered N -Flavor Dirac Fermions in Two Dimensions

Jean-Sébastien Caux

Published Nov 9, 1998• 37 citations
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Abstract

We present a nonperturbative calculation of all multifractal scaling exponents at strong disorder for critical wave functions of Dirac fermions interacting with a non-Abelian random vector potential in two dimensions. The results, valid for an arbitrary number of fermionic flavors, are obtained by deriving from conformal field theory an effective Gaussian model for the wave function amplitudes and mapping it to the thermodynamics of a single particle in a random potential. Our spectrum confirms that the wave functions remain delocalized in the presence of strong disorder.

DOI
10.1103/physrevlett.81.4196

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