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arXiv · 1803.08786

rf surface impedance of a two-gap superconductor, considering magnesium diboride for accelerator applications

Binping Xiao·C. E. Reece
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Abstract

In this paper, we apply the two-band extension [1] of BCS theory [2] into the Mattis-Bardeen theory [3] to obtain the surface impedance of a two-band superconductor, and apply it to magnesium diboride (MgB2) for radiofrequency (RF) superconductivity applications. The numerical results for MgB2 are in good agreement with the previously published experimental results [4]. The surface impedance properties are clearly dominated by the smaller gap, significantly limiting utility in the 10-20 K regime that might otherwise have been attractive.

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Binping Xiao, C. E. Reece. 2018-03-23. rf surface impedance of a two-gap superconductor, considering magnesium diboride for accelerator applications. https://doi.org/10.1103/physrevaccelbeams.22.053101

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