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Quantum and Thermal Depinning of a String from a Linear Defect

Mikhail A. Skvortsov
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Abstract

The problem of a massive elastic string depinning from a linear defect under the action of a small driving force is considered. To exponential accuracy the decay rate is calculated with the help of the instanton method; then, fluctuations of the quasiclassical solution are taken into account to determine the preexponential factor. The decay rate exhibits a kind of first order transition from quantum tunneling to thermal activation with vanishing crossover region. The model may be applied to describe nucleation in 2-dimensional first order quantum phase transitions.

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Mikhail A. Skvortsov. 1996-09-17. Quantum and Thermal Depinning of a String from a Linear Defect. https://doi.org/10.1103/physrevb.55.515

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