Short time scales in the Kramers problem: a stepwise growth of the escape flux.

Phys Rev Lett

Institute of Semiconductor Physics, Ukrainian National Academy of Sciences, Kiev, Ukraine.

Published: February 2001

We prove rigorously and demonstrate in simulations that, for a potential system staying initially at the bottom of a well, the escape flux over the barrier grows on times of the order of a period of eigenoscillation in a stepwise manner, provided that friction is small or moderate. If the initial state is not at the bottom of the well, then, typically, some of the steps transform into oscillations. The stepwise/oscillatory evolution at short times appears to be a generic feature of a noise-induced flux.

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http://dx.doi.org/10.1103/PhysRevLett.86.1665DOI Listing

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