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Dendritic magnetic instability in superconducting MgB2 films

T. H. Johansen·M. Baziljevich·D. V. Shantsev·P. E. Goa·Y. M. Galperin·W. N. Kang·H. J. Kim·E. M. Choi·M. -S. Kim·S. I. Lee
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Abstract

Magneto-opitcal studies of a c-oriented epitaxial MgB2 film show that below 10 K the global penetration of vortices is dominated by complex dendritic structures abruptly entering the film. We suggest that the observed behavior is due to a thermo-magnetic instability which is supported by vortex dynamics simulations. The instability is also responsible for large fluctuations in the magnetization curves in MgB2 at low temperatures.

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T. H. Johansen, M. Baziljevich, D. V. Shantsev, P. E. Goa, Y. M. Galperin, W. N. Kang, H. J. Kim, E. M. Choi, M. -S. Kim, S. I. Lee. 2001-07-18. Dendritic magnetic instability in superconducting MgB2 films. https://doi.org/10.1209/epl%2Fi2002-00146-1

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