Kramers escape rate in nonlinear diffusive media.

Zhao JiangLin; Jing-Dong Bao; Gong Wenping

doi:10.1063/1.2150433

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Kramers escape rate in nonlinear diffusive media.

Zhao JiangLin·Jing-Dong Bao·Gong Wenping

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Abstract

In this paper, we study nonlinear Kramers problem by investigating overdamped systems ruled by the one-dimensional nonlinear Fokker-Planck equation. We obtain an analytic expression for the Kramers escape rate under quasistationary conditions by employing a metastable potential and its predictions are in excellent agreement with numerical simulations. The results exhibit the anomalies due to the nonlinearity in W that the escape rate grows with D and drops as mu becomes large at a fixed D. Indeed, particles in the subdiffusive media (mu>1) can escape over the barrier only when D is above a critical value, while this confinement does not exist in the superdiffusive media (mu<1).

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Algorithms Chemistry, Physical Diffusion Energy Transfer Models, Chemical Models, Molecular Models, Statistical Models, Theoretical Nonlinear Dynamics Stochastic Processes Thermodynamics Time Factors Journal Article Research Support, Non-U.S. Gov't

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Zhao JiangLin, Jing-Dong Bao, Gong Wenping. 2006-01-14. Kramers escape rate in nonlinear diffusive media.. https://doi.org/10.1063/1.2150433

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