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

M. Yu. Kagan·R. Fresard·M. Capezzali·H. Beck
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Abstract

We calculate the one-electron spectral function of the attractive-U Hubbard model in two dimensions. We work in the intermediate coupling and low density regime and evaluate analytically the self-energy. The results are obtained in a framework based on the self-consistent T-matrix approximation. We also calculate the chemical potential of the bound pairs as a function of temperature. On the basis of this calculation we analyze the low-temperature resistivity and specific heat in the normal state of this system. We compare our results with recent beautiful tunneling experiments in the underdoped regime of HTSC-materials.

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M. Yu. Kagan, R. Fresard, M. Capezzali, H. Beck. 1999-11-22. One-electron spectral functions of the attractive Hubbard model at intermediate coupling. https://doi.org/10.1016/s0921-4526(99)02018-9

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