Excitation spectrum of the two-dimensional attractive Hubbard model

Massimiliano Capezzali; Hans Beck

doi:10.1016/s0921-4534(99)00104-5

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Excitation spectrum of the two-dimensional attractive Hubbard model

Massimiliano Capezzali·Hans Beck

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Abstract

We calculate the one-particle spectral functions above the superconducting transition temperature $T_{C}$, in the framework of a functional integral approach. The coupling of the electronic self-energy to pair fluctuations, which are treated by means of a time-dependent Ginzburg-Landau equation, yields a double-peak structure, around the Fermi wavenumber. The peak separation is essentially temperature-independent, but the structure sharpens when $T_{C}$ is approached.

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Massimiliano Capezzali, Hans Beck. 1998-09-25. Excitation spectrum of the two-dimensional attractive Hubbard model. https://doi.org/10.1016/s0921-4534(99)00104-5

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