Self-organized criticality in the Bean state in YBa$_2$Cu$_3$O$_{7-x}$ thin films

C. M. Aegerter; M. S. Welling; R. J. Wijngaarden

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Self-organized criticality in the Bean state in YBa$_2$Cu$_3$O$_{7-x}$ thin films

C. M. Aegerter·M. S. Welling·R. J. Wijngaarden

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Abstract

The penetration of magnetic flux into a thin film of YBa$_2$Cu$_3$O$_{7-x}$ is studied when the external field is ramped slowly. In this case the flux penetrates in bursts or avalanches. The size of these avalanches is distributed according to a power law with an exponent of $τ$ = 1.29(2). The additional observation of finite-size scaling of the avalanche distributions, with an avalanche dimension D = 1.89(3), gives strong indications towards self-organized criticality in this system. Furthermore we determine exponents governing the roughening dynamics of the flux surface using some universal scaling relations. These exponents are compared to those obtained from a standard roughening analysis.

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C. M. Aegerter, M. S. Welling, R. J. Wijngaarden. 2003-05-26. Self-organized criticality in the Bean state in YBa$_2$Cu$_3$O$_{7-x}$ thin films. https://arxiv.org/abs/cond-mat/0305591

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