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arXiv · 0802.0991

Correlation-induced metal insulator transition in a two-channel fermion-boson model

G. Wellein·H. Fehske·A. Alvermann·D. M. Edwards
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Abstract

We investigate charge transport within some background medium by means of an effective lattice model with a novel form of fermion-boson coupling. The bosons describe fluctuations of a correlated background. By analyzing groundstate and spectral properties of this transport model, we show how a metal-insulator quantum phase transition can occur for the half-filled band case. We discuss the evolution of a mass-asymmetric band structure in the insulating phase and establish connections to the Mott and Peierls transition scenarios.

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G. Wellein, H. Fehske, A. Alvermann, D. M. Edwards. 2008-08-24. Correlation-induced metal insulator transition in a two-channel fermion-boson model. https://doi.org/10.1103/physrevlett.101.136402

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