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arXiv · 2308.03681

Analytic density of states of two-dimensional Chern insulator

Vera Uzunova·Krzysztof Byczuk
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Abstract

We present analytic expressions for the density of states and its consistent derivation for the two-dimensional Qi-Wu-Zhang (QWZ) Hamiltonian, a generic model for the Chern topological insulators of class A. This density of states is expressed in terms of elliptical integrals. We discuss and plot special cases of the dispersion relations and the corresponding densities of states. Spectral moments are also presented. The exact formulae ought to be useful in determining physical properties of the non-interacting Chern insulators and within the dynamical mean-field theory for interacting fermions with the QWZ Hamiltonian in the non-interacting limit.

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Vera Uzunova, Krzysztof Byczuk. 2023-08-07. Analytic density of states of two-dimensional Chern insulator. https://doi.org/10.1103/physrevb.108.195131

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