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Depinning in a Random Medium

H. Kinzelbach·M. Lassig
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Abstract

We develop a renormalized continuum field theory for a directed polymer interacting with a random medium and a single extended defect. The renormalization group is based on the operator algebra of the pinning potential; it has novel features due to the breakdown of hyperscaling in a random system. There is a second-order transition between a localized and a delocalized phase of the polymer; we obtain analytic results on its critical pinning strength and scaling exponents. Our results are directly related to spatially inhomogeneous Kardar-Parisi-Zhang surface growth.

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H. Kinzelbach, M. Lassig. 1994-06-08. Depinning in a Random Medium. https://doi.org/10.1088/0305-4470%2F28%2F23%2F009

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