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Microwave surface resistance in superconductors with grain boundaries

Yasunori Mawatari
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Abstract

Microwave-field distribution, dissipation, and surface impedance are theoretically investigated for superconductors with laminar grain boundaries (GBs). In the present theory we adopt the two-fluid model for intragrain transport current in the grains, and the Josephson-junction model for intergrain tunneling current across GBs. Results show that the surface resistance $R_s$ nonmonotonically depends on the critical current density $J_{cj}$ at GB junctions, and $R_s$ for superconductors with GBs can be smaller than the surface resistance $R_{s0}$ for ideal homogeneous superconductors without GBs.

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Yasunori Mawatari. 2005-01-11. Microwave surface resistance in superconductors with grain boundaries. https://arxiv.org/abs/cond-mat/0501225

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