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arXiv · 2210.09356

Microscopic Derivation of Ginzburg-Landau Theory and the BCS Critical Temperature Shift in General External Fields

Andreas Deuchert·Christian Hainzl·Marcel Maier
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Abstract

We consider the Bardeen-Cooper-Schrieffer (BCS) free energy functional with weak and macroscopic external electric and magnetic fields and derive the Ginzburg-Landau functional. We also provide an asymptotic formula for the BCS critical temperature as a function of the external fields. This extends our previous results in arXiv:2105.05623 for the constant magnetic field to general magnetic fields with a nonzero magnetic flux through the unit cell.

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Andreas Deuchert, Christian Hainzl, Marcel Maier. 2022-10-17. Microscopic Derivation of Ginzburg-Landau Theory and the BCS Critical Temperature Shift in General External Fields. https://doi.org/10.1007/s00526-023-02539-x

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