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arXiv · 1809.01837

Dimensionality-induced BCS-BEC crossover in layered superconductors

Kyosuke Adachi·Ryusuke Ikeda
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Abstract

Based on a simple model of a layered superconductor with strong attractive interaction, we find that the separation of the pair-condensation temperature from the pair-formation temperature becomes more remarkable as the interlayer hopping gets smaller. We propose from this result the BCS-BEC crossover induced by the change in dimensionality, for instance, due to insertion of additional insulating layers or application of uniaxial pressure. The emergence of a pseudogap in the electronic density of states, which supports the idea of the dimensionality-induced BCS-BEC crossover, is also verified.

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Kyosuke Adachi, Ryusuke Ikeda. 2018-09-06. Dimensionality-induced BCS-BEC crossover in layered superconductors. https://doi.org/10.1103/physrevb.98.184502

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