Microwave-enhanced superconductivity and transport properties of Y-Ba-Cu-O bicrystal weak-links

The effects of the tilt angle on microwave-enhanced transition temperatures and critical currents of YBCO bicrystal weak-links have been investigated. It was found that, with smaller grain boundary tilt angles (e.g. 24/spl deg/), the enhancement was small, displaying essentially the same behavior as that manifested in intragranular regions. By contrast, when the tilt angle was increased from 36.8/spl deg/ to 45/spl deg/, noticeable Tc enhancement was found to occur even at low input microwave powers. The results were compared to the temperature dependent critical current, in order to delineate possible correlations between the two physical parameters.<
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