https://doi.org/10.1007/s100510050165
Evolution from BCS superconductivity to Bose condensation: analytic results for the crossover in three dimensions
1
Dipartimento di Matematica e Fisica, Sezione INFM,
Università di Camerino, 62032 Camerino, Italy
2
Institut Laue-Langevin,
BP 156, 38043 Grenoble Cedex 9, France
Corresponding author: a pistoles@ill.fr
Received:
9
May
1997
Revised:
4
August
1997
Accepted:
6
November
1997
Published online: 15 January 1998
We provide an analytic solution for the mean-field equations and for the relevant physical quantities at the Gaussian level, in terms of the complete elliptic integrals of the first and second kinds, for the crossover problem from BCS superconductivity to Bose-Einstein condensation of a three-dimensional system of free fermions interacting via an attractive contact potential at zero temperature. This analytic solution enables us to follow the evolution between the two limits in a particularly simple and transparent way, as well as to verify the absence of singularities during the evolution.
PACS: 74.20.-z – Theories and models of superconducting state / 74.20.Fg – BCS theory and its development / 67.40.-w – Boson degeneracy and superfluidity of 4He
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 1998
