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Singular Density of States of Disordered Dirac Fermions in the Chiral Models

Shinsei Ryu·Yasuhiro Hatsugai
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Abstract

The Dirac fermion in the random chiral models is studied which includes the random gauge field model and the random hopping model. We focus on a connection between continuum and lattice models to give a clear perspective for the random chiral models. Two distinct structures of density of states (DoS) around zero energy, one is a power-law dependence on energy in the intermediate energy range and the other is a diverging one at zero energy, are revealed by an extensive numerical study for large systems up to $250\times 250$. For the random hopping model, our finding of the diverging DoS within very narrow energy range reconciles previous inconsistencies between the lattice and the continuum models.

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Shinsei Ryu, Yasuhiro Hatsugai. 2001-07-25. Singular Density of States of Disordered Dirac Fermions in the Chiral Models. https://doi.org/10.1103/physrevb.65.033301

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