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Critical state in type-II superconductors of arbitrary shape

Grigorii P. Mikitik·Ernst Helmut Brandt
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Abstract

The well-known Bean critical state equations in general are not sufficient to describe the critical state of type-II superconductors when the sample shape is not symmetric. We show how one can find the critical state in superconductors of arbitrary shape. Analyzing a simple example of nonsymmetry, we demonstrate that in the general case, a perturbation of the current distribution in the critical state propagates into the sample smoothly in a diffusive way. This is in contrast to the usual Bean critical state where the current distribution changes abruptly at a narrow front.

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Grigorii P. Mikitik, Ernst Helmut Brandt. 2004-12-16. Critical state in type-II superconductors of arbitrary shape. https://doi.org/10.1103/physrevb.71.012510

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