Disorder-induced depinning transition.
نویسندگان
چکیده
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 ǫ-expansion.
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عنوان ژورنال:
- Physical review. B, Condensed matter
دوره 51 1 شماره
صفحات -
تاریخ انتشار 1995