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Published on: February 22, 2018
Escape rate of active particles in the effective equilibrium approach
A Sharma1, R Wittmann1, J M Brader1
1Department of Physics, University of Fribourg, CH-1700 Fribourg, Switzerland.
Abstract:
The escape rate of a Brownian particle over a potential barrier is accurately described by the Kramers theory. A quantitative theory explicitly taking the activity of Brownian particles into account has been lacking due to the inherently out-of-equilibrium nature of these particles. Using an effective equilibrium approach [Farage et al., Phys. Rev. E 91, 042310 (2015)PLEEE81539-375510.1103/PhysRevE.91.042310] we study the escape rate of active particles over a potential barrier and compare our analytical results with data from direct numerical simulation of the colored noise Langevin equation. The effective equilibrium approach generates an effective potential that, when used as input to Kramers rate theory, provides results in excellent agreement with the simulation data.
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