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Temperature Dependence of Even-Odd Effects in Small Superconducting Systems

R. Balian·H. Flocard·M. Veneroni
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Abstract

Generalized BCS equations which consistently include the projection on the particle-number parity are derived from a systematic variational method. Numerical solutions are given that are illustrative of ultra-small metallic grains. Compared to the BCS approximation, the pairing is slightly enhanced in even and noticeably inhibited in odd systems. In the latter case, the gap increases with T near T=0; for a suitably small pairing this can result in a reentrance phenomenon. Paramagnetic effects are evaluated as functions of the temperature and the magnetic field.

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R. Balian, H. Flocard, M. Veneroni. 1998-02-01. Temperature Dependence of Even-Odd Effects in Small Superconducting Systems. https://arxiv.org/abs/cond-mat/9802006

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