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Energy Barriers to Motion of Flux Lines in Random Media

Lev V. Mikheev·Barbara Drossel·Mehran Kardar
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Abstract

We propose algorithms for determining both lower and upper bounds for the energy barriers encountered by a flux line in moving through a two-dimensional random potential. Analytical arguments, supported by numerical simulations, suggest that these bounds scale with the length $t$ of the line as $t^{1/3}$ and $t^{1/3}\sqrt{\ln t}$, respectively. This provides the first confirmation of the hypothesis that barriers have the same scaling as the fluctuation in the free energy. \pacs{PACS numbers: 74.60.Ge, 05.70.Ln, 05.40.+j}

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Lev V. Mikheev, Barbara Drossel, Mehran Kardar. 1995-08-07. Energy Barriers to Motion of Flux Lines in Random Media. https://doi.org/10.1103/physrevlett.75.1170

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