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Structure change of Cooper pairs in color superconductivity -- Crossover from BCS to BEC ? --

Kazunori Itakura
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Abstract

We discuss a possibility of transition from color superconductivity of the standard BCS type at high density, to Bose-Einstein Condensation (BEC) of Cooper pairs at lower density. Examining two-flavor QCD over a wide range of baryon density, we found the size of a Cooper pair becomes small enough to be comparable to the averaged quark-quark distance at lower density. We also consider the same problem in two-color QCD.

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Kazunori Itakura. 2002-09-07. Structure change of Cooper pairs in color superconductivity -- Crossover from BCS to BEC ? --. https://doi.org/10.1016/s0375-9474(02)01523-3

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