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Anomalous Flux Pinning in ?-Pyrochlore Oxide Superconductor KOs2O6

Zenji Hiroi·Shigeki Yonezawa
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Abstract

The superconducting transition of the ?-pyrochlore oxide KOs2O6 with Tc = 9.60 K is studied by resistivity measurements under various magnetic fields using a high-quality single crystal. The reentrant behavior of superconductivity is observed near Tc in low magnetic fields below 2 T. The recovered resistance probably due to flux flow exhibits an anomalous angle dependence, indicating that flux pinning is enhanced in magnetic fields along certain crystallographic directions such as [110], [001] and [112]. It is suggested that there is an intrinsic pinning mechanism coming from the specific crystal structure of the ?-pyrochlore oxide.

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Zenji Hiroi, Shigeki Yonezawa. 2006-02-18. Anomalous Flux Pinning in ?-Pyrochlore Oxide Superconductor KOs2O6. https://doi.org/10.1143/jpsj.75.043701

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