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arXiv · 1008.0581

Is the term "type-1.5 superconductivity" warranted by Ginzburg-Landau theory?

V. G. Kogan·Joerg Schmalian
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Abstract

It is shown that within the Ginzburg-Landau (GL) approximation the order parameters Delta1(r, T) and Delta2(r, T) in two-band superconductors vary on the same length scale, the difference in the zero-T coherence lengths xi0_i ~vF_i/Delta_i(0), i = 1, 2 notwithstanding. This amounts to a single physical GL parameter kappa and the classic GL dichotomy: kappa < 1/sqrt(2) for type-I and kappa > 1/sqrt(2) for type-II.

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V. G. Kogan, Joerg Schmalian. 2011-01-03. Is the term "type-1.5 superconductivity" warranted by Ginzburg-Landau theory?. https://doi.org/10.1103/physrevb.83.054515

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