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Enhancement of superconductivity by local inhomogeneity

Ivar Martin·Daniel Podolsky·Steven A. Kivelson
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Abstract

We study the effect of inhomogeneity of the paring interaction or the background potential on the superconducting transition temperature, T_c. In the weak coupling BCS regime, we find that inhomogeneity which is incommensurate with the Fermi surface nesting vectors enhances T_c relative to its value for the uniform system. For a fixed modulation strength we find that the highest T_c is reached when the characteristic modulation length scale is of the order of the superconducting coherence length.

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Ivar Martin, Daniel Podolsky, Steven A. Kivelson. 2005-01-27. Enhancement of superconductivity by local inhomogeneity. https://doi.org/10.1103/physrevb.72.060502

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