BCS theory for trapped ultracold fermions
Department of Physics, Clarendon Laboratory, University of Oxford, Oxford OX1 3PU,
2 Laboratoire Kastler Brossel, École Normale Supérieure, 24 rue Lhomond, 75231 Paris Cedex 5, France
Published online: 15 October 1999
We develop an extension of the well-known BCS-theory to systems with trapped fermionic atoms. The theory fully includes the quantized energy levels in the trap. The key ingredient is to model the attractive interaction between two atoms by a pseudo-potential which leads to a well defined scattering problem and consequently to a BCS-theory free of divergences. We present numerical results for the BCS critical temperature and the temperature dependence of the gap. They are used as a test of existing semi-classical approximations.
PACS: 05.30.Fk – Fermion systems and electron gas / 03.75.Fi – Phase coherent atomic ensembles; quantum condensation phenomena / 32.80.Pj – Optical cooling of atoms; trapping
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 1999