Field-Theoretical description of the crossover between BCS and BEC in a non-Fermi superconductor

C. P. Moca; I. Tifrea; M. Crisan

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Field-Theoretical description of the crossover between BCS and BEC in a non-Fermi superconductor

C. P. Moca·I. Tifrea·M. Crisan

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Abstract

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 $\a\neq 0$ the crossover is also continous and for $\a=0$ we obtain the case of the Fermi liquid.

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C. P. Moca, I. Tifrea, M. Crisan. 1999-04-14. Field-Theoretical description of the crossover between BCS and BEC in a non-Fermi superconductor. https://arxiv.org/abs/cond-mat/9904197

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