Holstein model in infinite dimensions at half-filling
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چکیده
منابع مشابه
J ul 1 99 8 Holstein model in infinite dimensions at half - filling Patrizia Benedetti and Roland Zeyher
The normal state of the Holstein model is studied at half-filling in infinite dimensions and in the adiabatic regime. The dynamical mean-field equations are solved using perturbation expansions around the extremal paths of the effective action for the atoms. We find that the Migdal-Eliashberg expansion breaks down in the metallic state if the electron-phonon coupling λ exceeds a value of about ...
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ژورنال
عنوان ژورنال: Physical Review B
سال: 1998
ISSN: 0163-1829,1095-3795
DOI: 10.1103/physrevb.58.14320