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arXiv · 1202.0243

Efficiency of molecular machines with continuous phase space

N. Golubeva·A. Imparato·L. Peliti
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Abstract

We consider a molecular machine described as a Brownian particle diffusing in a tilted periodic potential. We evaluate the absorbed and released power of the machine as a function of the applied molecular and chemical forces, by using the fact that the times for completing a cycle in the forward and the backward direction have the same distribution, and that the ratio of the corresponding splitting probabilities can be simply expressed as a function of the applied force. We explicitly evaluate the efficiency at maximum power for a simple sawtooth potential. We also obtain the efficiency at maximum power for a broad class of 2-D models of a Brownian machine and find that loosely coupled machines operate with a smaller efficiency at maximum power than their strongly coupled counterparts.

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N. Golubeva, A. Imparato, L. Peliti. 2012-02-29. Efficiency of molecular machines with continuous phase space. https://doi.org/10.1209/0295-5075%2F97%2F60005

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