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arXiv · cond-mat/9810013

BCS Theory for Trapped Ultracold Fermions

G. Bruun·Y. Castin·R. Dum·K. Burnett
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Abstract

We develop an extension of the well-known BCS-theory to systems with trapped fermions. 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 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.

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G. Bruun, Y. Castin, R. Dum, K. Burnett. 1998-10-01. BCS Theory for Trapped Ultracold Fermions. https://doi.org/10.1007/s100530050587

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