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arXiv · 0704.2310

Semiclassical Theory of Bardeen-Cooper-Schrieffer Pairing-Gap Fluctuations

H. Olofsson·S. Åberg·P. Leboeuf
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Abstract

Superfluidity and superconductivity are genuine many-body manifestations of quantum coherence. For finite-size systems the associated pairing gap fluctuates as a function of size or shape. We provide a parameter free theoretical description of pairing fluctuations in mesoscopic systems characterized by order/chaos dynamics. The theory accurately describes experimental observations of nuclear superfluidity (regular system), predicts universal fluctuations of superconductivity in small chaotic metallic grains, and provides a global analysis in ultracold Fermi gases.

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H. Olofsson, S. Åberg, P. Leboeuf. 2008-01-25. Semiclassical Theory of Bardeen-Cooper-Schrieffer Pairing-Gap Fluctuations. https://doi.org/10.1103/physrevlett.100.037005

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