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Further evidence for linearly-dispersive Cooper pairs

M. de Llano·J. J. Valencia
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Abstract

A recent Bose-Einstein condensation (BEC) model of several cuprate superconductors is based on bosonic Cooper pairs (CPs) moving in 3D with a quadratic energy-momentum (dispersion) relation. The 3D BEC condensate-fraction vs. temperature (T/Tc, where Tc is the BEC transition temperature) formula poorly fits penetration-depth data for two cuprates in the range (1/2, 1]. We show how these fits are dramatically improved assuming cuprates to be quasi-2D, and how equally good fits obtain for conventional 3D and quasi-1D nanotube superconducting data, provided the correct CP dispersion is assumed in BEC at their assumed corresponding dimensionalities. This is offered as additional concrete empirical evidence for linearly-dispersive pairs in another recent BEC scenario of superconductors within which a BCS condensate turns out to be a very special case.

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M. de Llano, J. J. Valencia. 2007-02-23. Further evidence for linearly-dispersive Cooper pairs. https://doi.org/10.1142/s021798490601158x

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