Spectral properties of the attractive Hubbard model
نویسندگان
چکیده
منابع مشابه
Some Properties of the Spin-Polarized Attractive Hubbard Model
The influence of a Zeeman magnetic field on the superconducting characteristics of the attractive Hubbard model has been investigated. The ground state and temperature phase diagrams have been obtained for a fixed number of particles. Two critical magnetic fields have been found for the first order phase transition from the superconducting (SC) to the normal (NO) state for n 6= 1. For some rang...
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B. Kyung, S. Allen, and A.-M. S. Tremblay Département de Physique and Centre de Recherche sur les Propriétés Électroniques de Matériaux Avancés, Université de Sherbrooke, Sherbrooke, Québec, Canada J1K 2R1 Institut Canadien de Recherches Avancées, Université de Sherbrooke, Sherbrooke, Québec, Canada J1K 2R1 ~Received 2 October 2000; revised manuscript received 2 March 2001; published 31 July 2001!
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We investigate the electronic and superconducting properties of a negative-U Hubbard model. For this purpose we evaluate a recently introduced variational theory based on Gutzwiller-correlated BCS wavefunctions. We find significant differences between our approach and standard BCS theory, especially for the superconducting gap. For small values of |U|, we derive analytical expressions for the o...
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ژورنال
عنوان ژورنال: Journal of Physics and Chemistry of Solids
سال: 1998
ISSN: 0022-3697
DOI: 10.1016/s0022-3697(98)00123-1