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A minimal size for granular superconductors

L. M. Abreu·A. P. C. Malbouisson·I. Roditi
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Abstract

We investigate the minimal size of small superconducting grains by means of a Ginzburg-Landau model confined to a sphere of radius $R$. This model is supposed to describe a material in the form of a ball, whose transition temperature when presented in bulk form, $T_{0}$, is known. We obtain an equation for the critical temperature as a function of $R$ and of $T_{0}$, allowing us to arrive at the minimal radius of the sphere below which no superconducting transition exists.

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L. M. Abreu, A. P. C. Malbouisson, I. Roditi. 2003-05-15. A minimal size for granular superconductors. https://doi.org/10.1016/j.physa.2003.09.032

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