Flux penetration in a superconducting strip with an edge indentation
نویسندگان
چکیده
The flux penetration near a semicircular indentation at the edge of a thin superconducting strip placed in a transverse magnetic field is investigated. The flux front distortion due to the indentation is calculated numerically by solving the Maxwell equations with a highly nonlinear E j law. We find that the excess penetration can be significantly 50% larger than the indentation radius r0, in contrast to a bulk superconductor in the critical state where =r0. It is also shown that the flux creep tends to smoothen the flux front, i.e., reduce . The results are in very good agreement with magneto-optical studies of flux penetration into an YBa2Cu3Ox film having an edge defect.
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