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arXiv · hep-th/0003015

A quantum Peierls-Nabarro barrier

J. M. Speight
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Abstract

Kink dynamics in spatially discrete nonlinear Klein-Gordon systems is considered. For special choices of the substrate potential, such systems support continuous translation orbits of static kinks with no (classical) Peierls-Nabarro barrier. It is shown that these kinks experience, nevertheless, a lattice-periodic confining potential, due to purely quantum effects anaolgous to the Casimir effect of quantum field theory. The resulting ``quantum Peierls-Nabarro potential'' may be calculated in the weak coupling approximation by a simple and computationally cheap numerical algorithm, which is applied, for purposes of illustration, to a certain two-parameter family of substrates.

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J. M. Speight. 2000-03-02. A quantum Peierls-Nabarro barrier. https://doi.org/10.1088/0305-4470%2F33%2F26%2F302

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