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Nucleation of Superconductivity in Thin Type-I Foils

P. Valko·M. R. Gomes·TA Girard
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Abstract

The nucleation of the superconductive phase in macroscopic type-I foils in a slow, continuously decreasing perpendicular magnetic field is observed to first occur at the field $H_{c3}$, and reinitiate at $H_{c2}$. The observed variation of $H_{c2}$ with temperature further yields Ginzburg-Landau parameters for the materials approximately a factor 2 below tabulations, consistent with previous determinations in small grains.

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P. Valko, M. R. Gomes, TA Girard. 2007-03-26. Nucleation of Superconductivity in Thin Type-I Foils. https://doi.org/10.1103/physrevb.75.140504

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