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arXiv · 1404.6139

Density of states in a two-dimensional chiral metal with vacancies

P. M. Ostrovsky·I. V. Protopopov·E. J. König·I. V. Gornyi·A. D. Mirlin·M. A. Skvortsov
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Abstract

We study quantum interference effects in a two-dimensional chiral metal (bipartite lattice) with vacancies. We demonstrate that randomly distributed vacancies constitute a peculiar type of chiral disorder leading to strong modifications of critical properties at zero energy as compared to conventional chiral metals. In particular, the average density of states diverges as $ρ\propto E^{-1} |\ln E|^{-3/2}$ and the correlation length $L_c \propto \sqrt{|\ln E|}$ in the limit $E \to 0$. When the average density of vacancies is different in the two sublattices, a finite concentration of zero modes emerges and a gap in the quasiclassical density of states opens around zero energy. Interference effects smear this gap resulting in exponentially small tails at low energies.

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P. M. Ostrovsky, I. V. Protopopov, E. J. König, I. V. Gornyi, A. D. Mirlin, M. A. Skvortsov. 2014-04-25. Density of states in a two-dimensional chiral metal with vacancies. https://doi.org/10.1103/physrevlett.113.186803

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