Superconducting transition of a two-dimensional Josephson junction array in weak magnetic fields

In-Cheol Baek; Young-Je Yun; Mu-Yong Choi

doi:10.1103/physrevb.72.144507

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Superconducting transition of a two-dimensional Josephson junction array in weak magnetic fields

In-Cheol Baek·Young-Je Yun·Mu-Yong Choi

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Abstract

The superconducting transition of a two-dimensional (2D) Josephson junction array exposed to weak magnetic fields has been studied experimentally. Resistance measurements reveal a superconducting-resistive phase boundary in serious disagreement with the theoretical and numerical expectations. Critical scaling analyses of the $IV$ characteristics indicate contrary to the expectations that the superconducting-to-resistive transition in weak magnetic fields is associated with a melting transition of magnetic-field-induced vortices directly from a pinned-solid phase to a liquid phase. The expected depinning transition of vortices from a pinned-solid phase to an intermediate floating-solid phase was not observed. We discuss effects of the disorder-induced random pinning potential on phase transitions of vortices in a 2D Josephson junction array.

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In-Cheol Baek, Young-Je Yun, Mu-Yong Choi. 2005-06-11. Superconducting transition of a two-dimensional Josephson junction array in weak magnetic fields. https://doi.org/10.1103/physrevb.72.144507

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