Nanosecond magneto-optic study of a new instability in thin YBa2Cu3O7-x films
نویسنده
چکیده
We have investigated the dynamics of flux penetration into thin superconducting YBa2Cu307--x films using a magneto-optic technique with nanosecond time resolution. For films carrying large shielding currents an instability in the magnetic Aux distribution is discovered, which can be triggered by a local’perturbation, e.g., by a focused laser pulse. The instability develops in the form of fine ramified flux structures, with a propagation speed of the flux front on the order of 5 X IO4 m/s.
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