Avalanches injecting flux into the central hole of a superconducting MgB2 ring

作者:Olsen Age Andreas Falnes*; Johansen Tom Henning; Shantsev Daniel; Choi Eun Mi; Lee Hyun Sook; Kim Hyun Jung; Lee Sung Ik
来源:Physical Review B, 2007, 76(2): 024510.
DOI:10.1103/PhysRevB.76.024510

摘要

Magneto-optical imaging was used to observe dendritic flux avalanches connecting the outer and inner edges of a ring-shaped superconducting MgB2 film. Such avalanches create heated channels across the entire width of the ring, and inject large amounts of flux into the central hole. By measuring the injected flux and the corresponding reduction of current, which is typically 15%, we estimate the maximum temperature in the channel to be 100 K, and the duration of the process to be on the order of a microsecond. Flux creep simulations reproduce all the observed features in the current density before and after injection events.

  • 出版日期2007-7