Low-frequency response in the surface superconducting state of single-crystal ZrB12

Hebrew University of Jerusalem, Yerushalayim, Jerusalem, Israel
Physical Review B (Impact Factor: 3.74). 02/2005; 71(6). DOI: 10.1103/PhysRevB.71.064506
Source: arXiv


A large nonlinear response of a single crystal of ZrB12 to an ac field (frequency 40–2500 Hz) for H0>Hc2 has been observed. Direct measurements of the ac wave form and the exact numerical solution of the Ginzburg-Landau equations, as well as the phenomenological relaxation equation, permit the study of the surface superconducting state dynamics. It is shown that the low-frequency response is defined by transitions between the metastable superconducting states under the action of an ac field. The relaxation rate that determines such transition dynamics is found.

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    • "−ln f according to the Kramers–Kronig relation. And it is just what was observed in the borides in the low-frequency limit [13] [14], see Fig. 2. Extension of such measurements to high frequencies would allow validation of the assumption about the barrier distribution function. "
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