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arXiv · 1304.4516

Dependence of the microwave surface resistance of superconducting niobium on the magnitude of the rf field

A. Romanenko·A. Grassellino
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Abstract

Utilizing difference in temperature dependencies we decoupled BCS and residual components of the microwave surface resistance of superconducting niobium at all rf fields up to $B_\mathrm{rf}\sim110$ mT. We reveal that the residual resistance decreases with field at $B_\mathrm{rf} \lesssim$ 40 mT and strongly increases in chemically treated niobium at $B_\mathrm{rf} > 80$ mT. We find that BCS surface resistance is weakly dependent on field in the clean limit, whereas a strong and peculiar field dependence emerges after $120^\circ$C vacuum baking.

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A. Romanenko, A. Grassellino. 2013-04-16. Dependence of the microwave surface resistance of superconducting niobium on the magnitude of the rf field. https://doi.org/10.1063/1.4812665

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