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arXiv · 2212.06333

A forced thermal ratchet in a memory heat bath

O. Contreras-Vergara·N. Sánchez-Salas·I. Pérez Castillo·J. I. Jiménez-Aquino
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Abstract

The present work studies a non-Markovian forced thermal ratchet model on an asymmetric periodic potential. The Brownian dynamics is described by a generalized Langevin equation with an Ornstein-Uhlenbeck-type friction memory kernel. We show that for the case of a time-dependent driving force, also in the form of an Ornstein-Uhlenbeck-like process, an exact expression of the probability current can be derived. We also obtain the behavior of the particle's average rate of flow as a function of the external amplitude force and of the bath temperature when the driving force behaves as a square wave modulation. All our results are compared with those obtained in the Markovian case and we find, fairly remarkably, that in some cases a friction memory kernel results in an enhancement of the current

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O. Contreras-Vergara, N. Sánchez-Salas, I. Pérez Castillo, J. I. Jiménez-Aquino. 2022-12-13. A forced thermal ratchet in a memory heat bath. https://arxiv.org/abs/2212.06333

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