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High-Tc Superconductivity via BCS and BEC Unification: A Review

M. de Llano
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Abstract

Though commonly unrecognized, a superconducting BCS condensate consists of equal numbers of two-electron (2e) and two-hole (2h) Cooper pairs (CPs). A complete (in the sense that 2h-CPs are not ignored) boson-fermion statistical model, however, is able to depart from this perfect 2e-/2h-CP symmetry and yields robustly higher T_c's without abandoning electron-phonon dynamics. The complete model reduces to all the known statistical theories of superconductors, including the BCS-Bose "crossover" picture but going considerably beyond it.

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M. de Llano. 2004-05-04. High-Tc Superconductivity via BCS and BEC Unification: A Review. https://arxiv.org/abs/cond-mat/0405071

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