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Single-particle spectrum for a model of fermions interacting with two-level local excitations on a lattice: A dynamical CPA approach

A. O. Anokhin·A. V. Zarubin·V. Yu. Irkhin
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Abstract

The problem of motion of a single electron interacting with a periodic lattice of two-level systems is investigated within a spinless fermion model. The Green's function is calculated in a single-site dynamical coherent potential approximation which is equivalent to DMFT. The picture of one-electron density of states is obtained for various values of the tunnel splitting and coupling between the electron and two-level system. The occurrence of a band splitting with increase of the coupling is demonstrated.

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A. O. Anokhin, A. V. Zarubin, V. Yu. Irkhin. 2006-05-02. Single-particle spectrum for a model of fermions interacting with two-level local excitations on a lattice: A dynamical CPA approach. https://doi.org/10.1016/j.physleta.2006.04.058

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