New reentrant superconducting-normal transition in Sr1−xKxBiO3 superconductor: magnetotransport and magnetization study

• Published in: Physica. C, Superconductivity Superconductivity, 2000-11, Vol.341-348, p.797-800
• Main Authors: Kim, D.C., Kim, J.S., Joo, S.J., Kim, G.T., Bougerol-Chaillout, C., Kazakov, S.M., Pshirkov, J.S., Antipov, E.V., Park, Y.W.
• Format: Article
• Language: English
• ISSN: 0921-4534
• DOI: 10.1016/S0921-4534(00)00698-5

Authors report a new reentrant superconducting-normal resistive transition observed in the Sr1-xKxBiO3 superconductor. Unlike previous reports about the reentrant resistive transition, where the superconducting region becomes reduced and finally resumes the normal state by increasing the external magnetic field (H) or the current (I), authors observed the recovery of superconductivity induced by applying H or increasing I. Subsequent dc magnetization measurement shows a gradual decrease of the diamagnetic susceptibility--appearance of the paramagnetic Meissner effect--at low fields (H < 50 Oe) in the same temperature range where the reentrant normal resistivity was measured. Sample dependence of the reentrant resistive transition suggests the important role of grain boundaries in the samples. Possible physical origins of the field induced superconductivity observed in Sr1-xKxBiO3 are discussed. 14 refs.