One-electron spectral functions of the attractive Hubbard model for intermediate coupling

Article

关键词: COHERENCE LENGTH SUPERCONDUCTORS;    SELF-CONSISTENT THEORY;    BCS-SUPERCONDUCTIVITY;    CHARGE FLUCTUATIONS;    BOSE-CONDENSATION;    2 DIMENSIONS;    SPIN;    EXCITATION;    CROSSOVER;   

DOI  :  10.1103/PhysRevB.57.5995

来源: SCIE

【 摘 要 】

We calculate the one-electron spectral function of the attractive (negative-U) Hubbard model. We work in the intermediate-coupling and low-density regime and obtain the self-energy in an approximate analytical form. The excitation spectrum is found to consist of three branches. The results are obtained in a framework based on the self-consistent T-matrix approximation, which is compatible with the Mermin-Wagner theorem.

【 授权许可】

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