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Hysteresis measurement of anomalous microwave surface resistance in superconducting thin films

X. S. Rao·C. K. Ong·B. B. Jin·Y. P. Feng
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Abstract

The anomalous decrease in microwave surface resistance, R_{s}, of superconducting YBa_{2}Cu_{3}O_{7-d} (YBCO) thin films in the presence of a low dc magnetic field is studied using a microstrip resonator technique. We have done a dc field hysteresis measurement of R_{s} to study the effects of vortex penetration on the anomalous effect. It is shown that the anomaly happens at a field level far below the low critical field, H_{c1,strip}, of the superconducting microstrip and vortex (Abrikosov) penetration would eliminate the anomalous effect observed at low field. This implies that the anomalous effect is not contributed by vortices.

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X. S. Rao, C. K. Ong, B. B. Jin, Y. P. Feng. 2000-01-21. Hysteresis measurement of anomalous microwave surface resistance in superconducting thin films. https://doi.org/10.1016/s0921-4534(00)01493-3

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