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Phenomenological Model of the Nonlinear Microwave Response of a Superconductor Containing Weak Links

Anton V. Velichko·Adrian Porch
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Abstract

A phenomenological model is proposed which describes the effect of both dc and rf magnetic fields, $H$, on the microwave surface impedance, Z_s=R_s+jX_s, of a superconductor containing weak link. Two cases are considered; a weak link between two grains, shunted by another grain, and a non-shunted weak link. In both cases the dependences of R_s and X_s on applied field H were found to be anomalous. Under certain conditions, the values of Z_s(H) can fall below the zero-field values. Comparison with experiment is performed, and very good qualitative and (in some cases) quantitative agreement is found.

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Anton V. Velichko, Adrian Porch. 2000-10-05. Phenomenological Model of the Nonlinear Microwave Response of a Superconductor Containing Weak Links. https://arxiv.org/abs/cond-mat/9903304

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