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Disorder-Induced Depinning Transition

Terence Hwa·Thomas Nattermann
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Abstract

The competition in the pinning of a directed polymer by a columnar pin and a background of random point impurities is investigated systematically using the renormalization group method. With the aid of the mapping to the noisy-Burgers' equation and the use of the mode-coupling method, the directed polymer is shown to be marginally localized to an arbitrary weak columnar pin in 1+1 dimensions. This weak localization effect is attributed to the existence of large scale, nearly degenerate optimal paths of the randomly pinned directed polymer. The critical behavior of the depinning transition above 1+1 dimensions is obtained via an $ε$-expansion.

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Terence Hwa, Thomas Nattermann. 1994-04-12. Disorder-Induced Depinning Transition. https://doi.org/10.1103/physrevb.51.455

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