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Two-dimensional Bose-Einstein Condensation in Cuprate Superconductors

M. Casas·M. de Llano·A. Puente·A. Rigo·M. A. Solis
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Abstract

Transition temperatures $T_{c}$ calculated using the BCS model electron-phonon interaction without any adjustable parameters agree with empirical values for quasi-2D cuprate superconductors. They follow from a two-dimensional gas of temperature-dependent Cooper pairs in chemical and thermal equilibrium with unpaired fermions in a boson-fermion (BF) statistical model as the Bose-Einstein condensation (BEC) singularity temperature is approached from above. The {\it linear} (as opposed to quadratic) boson dispersion relation due to the Fermi sea yields substantially higher $T_{c}$'s with the BF model than with BCS or pure-boson BEC theories.

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M. Casas, M. de Llano, A. Puente, A. Rigo, M. A. Solis. 2001-10-18. Two-dimensional Bose-Einstein Condensation in Cuprate Superconductors. https://doi.org/10.1016/s0038-1098(02)00240-5

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