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arXiv · 1208.1651

Langevin dynamics with a tilted periodic potential

Gioia Carinci·Stephan Luckhaus
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Abstract

We study a Langevin equation for a particle moving in a periodic potential in the presence of viscosity $γ$ and subject to a further external field $α$. For a suitable choice of the parameters $α$ and $γ$ the related deterministic dynamics yields heteroclinic orbits. In such a regime, in absence of stochastic noise both confined and unbounded orbits coexist. We prove that, with the inclusion of an arbitrarly small noise only the confined orbits survive in a sub-exponential time scale.

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Gioia Carinci, Stephan Luckhaus. 2013-12-01. Langevin dynamics with a tilted periodic potential. https://doi.org/10.1007/s10955-013-0721-0

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