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Interplay between local electron correlation and Janh-Teller electron-phonon interaction

Choong H. Kim·Hyun C. Lee
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Abstract

The infinite-$U$ Anderson model coupled to a Jahn-Teller phonon is studied using the slave boson method on the basis of the large degeneracy expansion (1/N) scheme. The model Hamiltonian acts on the orbital degrees of freedom. The main focus is on the interplay between strong local electron correlation and weak Jahn-Teller electron-phonon interaction. The Kondo temperature is found to decrease by Jahn-Teller interaction. The influence of the Jahn-Teller interaction on dynamical correlation functions is very significant in sharp contrast with the case of the Holstein-type phonon which couples to charge degrees of freedom.

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Choong H. Kim, Hyun C. Lee. 2006-03-17. Interplay between local electron correlation and Janh-Teller electron-phonon interaction. https://doi.org/10.1103/physrevb.73.113109

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