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rf-studies of vortex dynamics in isotropic type-II superconductors

N. Lutke-Entrup·B. Placais·P. Mathieu·Y. Simon
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Abstract

We have measured the surface impedance of thick superconductors in the mixed state over a broad 2 kHz - 20 MHz frequency range. The depinning cross-over is observed; but it is much broader than expected from classical theories of pinning. A striking result is the existence of size effects which invalidate the common interpretation of the low-frequency surface inductance in terms of a single penetration depth. Instead, a two-mode description of vortex dynamics, assuming free vortex flow in the bulk and surface pinning, accounts quantitatively for the spectrum of the complex apparent penetration depth.

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N. Lutke-Entrup, B. Placais, P. Mathieu, Y. Simon. 1998-05-07. rf-studies of vortex dynamics in isotropic type-II superconductors. https://doi.org/10.1016/s0921-4526(98)00455-4

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