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Influence of surface irregularities on barriers for vortex entry in type-II superconductors

A. Yu. Aladyshkin·A. S. Mel'nikov·I . A. Shereshevsky·I. D. Tokman
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Abstract

A theoretical description of the influence of surface irregularities (such as wedge-like cracks) on the Bean-Livingston energy barrier is presented. A careful quantitative estimate of the field of the first vortex entry H* into a homogeneous bulk superconductor with crack-like defects is obtained. This estimate is based on an exact analytical solution for the Meissner current distribution in a bulk superconductor with a single two-dimensional infinitely thin crack. This thin crack is characterized by the lowest H* value, and, thus, appears to be the best gate for vortex entry.

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A. Yu. Aladyshkin, A. S. Mel'nikov, I . A. Shereshevsky, I. D. Tokman. 2000-11-04. Influence of surface irregularities on barriers for vortex entry in type-II superconductors. https://arxiv.org/abs/cond-mat/9911430

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