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Vortex core shrinkage in a two gap superconductor: application to MgB2

S. Graser·A. Gumann·T. Dahm·N. Schopohl
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Abstract

As a model for the vortex core in MgB2 we study a two band model with a clean sigma band and a dirty pi band. We present calculations of the vortex core size in both bands as a function of temperature and show that there exists a Kramer-Pesch effect in both bands even though only one of the bands is in the clean limit. We present calculations for different pi band diffusivities and coherence lengths.

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S. Graser, A. Gumann, T. Dahm, N. Schopohl. 2006-07-24. Vortex core shrinkage in a two gap superconductor: application to MgB2. https://doi.org/10.1016/j.physc.2007.04.103

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