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arXiv · 1903.01155

Superconducting size effect in thin films under electric field: mean-field self-consistent model

P. Virtanen·A. Braggio·F. Giazotto
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Abstract

We consider effects of an externally applied electrostatic field on superconductivity, self-consistently within a BCS mean field model, for a clean 3D metal thin film. The electrostatic change in superconducting condensation energy scales as $μ^{-1}$ close to subband edges as a function of the Fermi energy $μ$, and follows 3D scaling $μ^{-2}$ away from them. We discuss nonlinearities beyond gate effect, and contrast results to recent experiments.

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P. Virtanen, A. Braggio, F. Giazotto. 2019-03-04. Superconducting size effect in thin films under electric field: mean-field self-consistent model. https://doi.org/10.1103/physrevb.100.224506

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