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Superconductivity as a Bose-Einstein condensation?

S. K. Adhikari·M. Casas·A. Puente·A. Rigo·M. Fortes·M. A. Solís·M. de Llano·A. A. Valladares·O. Rojo
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Abstract

Bose-Einstein condensation (BEC) in two dimensions (2D) (e.g., to describe the quasi-2D cuprates) is suggested as the possible mechanism widely believed to underlie superconductivity in general. A crucial role is played by nonzero center-of-mass momentum Cooper pairs (CPs) usually neglected in BCS theory. Also vital is the unique {\it linear} dispersion relation appropriate to weakly-coupled "bosonic" CPs moving in the Fermi sea--rather than in vacuum where the dispersion would be quadratic but only for very strong coupling, and for which BEC is known to be impossible in 2D.

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S. K. Adhikari, M. Casas, A. Puente, A. Rigo, M. Fortes, M. A. Solís, M. de Llano, A. A. Valladares, O. Rojo. 2000-04-13. Superconductivity as a Bose-Einstein condensation?. https://doi.org/10.1016/s0921-4534(00)00457-3

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