Absorbed driven diffusion can provide positive heat and work output

Abstract

We investigate overdamped Brownian motion in a fluctuating potential on a one-dimensional interval bordered by absorbing boundaries. The potential switches randomly between the ∨-shaped and the ∧-shaped form and is symmetric with respect to the origin. We derive exact expressions describing the absorption process, dynamics and stochastic energetics of the particle. The mean absorption time can exhibit a pronounced minimum as the function of the potential switching rate. Moreover, there exists a parameter region where both the output work and the released heat are positive. We give a plausible explanation for this phenomenon based on typical statistical features of absorbed trajectories. The presented analytical method can be generalized to other models based on dichotomous switching between two potential shapes.