Strong Coupling Limit of the Holstein-Hubbard Model
نویسندگان
چکیده
منابع مشابه
Strong-coupling expansions for the anharmonic Holstein model and for the Holstein-Hubbard model.
A strong-coupling expansion is applied to the anharmonic Holstein model and to the Holstein-Hubbard model through fourth order in the hopping matrix element. Mean-field theory is then employed to determine transition temperatures of the effective (pseudospin) Hamiltonian. We find that anharmonic effects are not easily mimicked by an on-site Coulomb repulsion, and that anharmonicity strongly fav...
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A strong-coupling expansion for the Holstein (electron-phonon) model is carried out through fourth order. In the large frequency limit the expansion agrees with known results for the attractive Hubbard model. Mean-eld theory is employed to determine transition temperatures of the eeective (pseudospin) Hamiltonian and the results are compared with recent Monte Carlo simulations of these models i...
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ژورنال
عنوان ژورنال: Physical Review Letters
سال: 2020
ISSN: 0031-9007,1079-7114
DOI: 10.1103/physrevlett.125.167001