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Magnetic Penetration Depth and Surface Resistance in YBa_2Cu_3O_{7-delta}: New Results for Ultra High Purity Crystals

S. Kamal·Ruixing Liang·A. Hosseini·D. A. Bonn·W. N. Hardy
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Abstract

We have succeeded in growing very high purity (99.995%) YBa_2Cu_3O_{7-delta} crystals in BaZrO_3 crucibles and have measured Delta-lambda(T) and R_s(T) at 1 GHz in crystals with various oxygen treatments. For an oxygen vacancy level of delta=0.007, Delta-lambda and R_s essentially reproduce our previous results and show no sign of the existence of the two order parameter components as recently reported by Srikanth et al. on BaZrO_3-grown crystals. For other oxygen concentrations, we have in some cases observed deviations from the linear low T dependence of Delta-lambda, but never any sign of a second transition.

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S. Kamal, Ruixing Liang, A. Hosseini, D. A. Bonn, W. N. Hardy. 1998-03-24. Magnetic Penetration Depth and Surface Resistance in YBa_2Cu_3O_{7-delta}: New Results for Ultra High Purity Crystals. https://arxiv.org/abs/cond-mat/9803292

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