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Anisotropic Scattering Rates in the t-t'-U Hubbard Model

Joachim Altmann·Wolfram Brenig·Arno P. Kampf
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Abstract

We have investigated the evolution of the electronic properties of the t-t'-U Hubbard model with hole doping and temperature. Due to the shape of the Fermi surface, scattering from short wavelength spin fluctuations leads to strongly anisotropic quasi-particle scattering rates at low temperatures near half-filling. As a consequence, significant variations with momenta near the Fermi surface emerge for the spectral functions and the corresponding ARPES signals. This behavior is quite in contrast to the intermediate doping regime and we discuss the possible relevance of our results for the interpretation of photoemission spectra in cuprate superconductors at different hole doping levels.

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Joachim Altmann, Wolfram Brenig, Arno P. Kampf. 1997-07-25. Anisotropic Scattering Rates in the t-t'-U Hubbard Model. https://arxiv.org/abs/cond-mat/9707267

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