Field-Theoretical description of the crossover between BCS and BEC in a non-Fermi superconductor
نویسنده
چکیده
Using the field-theoretical methods we studied the evolution from BCS description of a non-Fermi superconductor to that of Bose-Einstein condensation (BEC) in one loop approximation. We showed that the repulsive interaction between composite bosons is determined by the exponent α of the Anderson propagator in a two dimensional model. For α 6= 0 the crossover is also continous and for α = 0 we obtain the case of the Fermi liquid. Typeset using REVTEX 1
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