Microwave response of YBa2Cu3O6.95 crystals: Evidence for a multicomponent order parameter
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چکیده
New features are reported in precision measurements of the complex microwave conductivity of high-quality YBa2Cu3O6.95 crystals grown in BaZrO3 crucibles. A third peak in the normal conductivity, s1(T), at around 80 K, and enhanced pair conductivity s2(T) below ;65 K are observed. The data are inconsistent with a single order parameter, and instead are indicative of multicomponent superconductivity. Overall, these results point to the presence of multiple pairing interactions in YBa2Cu3O6.95 and also provide a natural explanation to account for the low-temperature 35-K conductivity peak observed in all YBa2Cu3O6.95 crystals. @S0163-1829~97!52322-8#
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تاریخ انتشار 1997