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The Gradient Expansion for the Free-Energy of a Clean Superconductor

Simon Kos·Michael Stone
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Abstract

We describe a novel method for obtaining the gradient expansion for the free energy of a clean BCS superconductor. We present explicit results up to fourth order in the gradients of the order parameter.

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Simon Kos, Michael Stone. 1998-09-12. The Gradient Expansion for the Free-Energy of a Clean Superconductor. https://doi.org/10.1103/physrevb.59.9545

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