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

Article

关键词: FRUSTRATED-XY MODEL;    PHASE-TRANSITIONS;    VORTEX-LATTICE;    WIRE NETWORKS;    BEHAVIOR;   

DOI  :  10.1103/PhysRevB.72.144507

来源: SCIE

【 摘 要 】

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. Measurements 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.

【 授权许可】

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