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arXiv · 0906.3865

Interplay of electron-phonon interaction and strong correlations: DMFT+Σstudy

E. Z. Kuchinskii·I. A. Nekrasov·M. V. Sadovskii
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Abstract

We perform investigation of Hubbard model with interaction between strongly correlated conducting electrons on a lattice with Debye phonons. To solve the problem generalized dynamical mean-field DMFT+Σmethod is employed with "external" self-energy Σ_ph corresponding to electron-phonon interaction. We present DMFT+Σ_ph results for densities of states and kinks in energy dispersions for a variety of model parameters, analyzing the interplay of recently discovered kinks of purely electronic nature and usual phonon kinks in the electronic spectrum.

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E. Z. Kuchinskii, I. A. Nekrasov, M. V. Sadovskii. 2009-06-21. Interplay of electron-phonon interaction and strong correlations: DMFT+Σstudy. https://doi.org/10.1103/physrevb.80.115124

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