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arXiv · 2305.09283

Mechanism for giant enhancement of transport induced by active fluctuations

Abstract

Understanding the role of active fluctuations in physics is a problem in statu nascendi appearing both as a hot topic and a major challenge. The reason for this is the fact that they are inherently non-equilibrium. This feature opens a landscape of phenomena yet to be explored that are absent in the presence of thermal fluctuations alone. Recently a paradoxical effect has been briefly communicated in which a free particle transport induced by active fluctuations in the form white Poisson shot noise can be enormously boosted when the particle is additionally subjected to a periodic potential. In this work we considerably extend the original predictions and investigate the impact of statistics of active noise on the occurrence of this effect. We construct a toy-model of the jump-relaxation process that allow us to identify different regimes of the free particle transport boost and explain their corresponding mechanisms. Moreover, we formulate and interpret the conditions for statistics of active fluctuations that are necessary for the emergence of giant enhancement of the free particle transport induced by the periodic potential. Our results are relevant not only for microscopic physical systems but also for biological ones such as e.g. living cells where fluctuations generated by metabolic activities are active by default.

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BibTeXRIS

Karol Białas, Jakub Spiechowicz. 2023-05-16. Mechanism for giant enhancement of transport induced by active fluctuations. https://doi.org/10.1103/physreve.107.064120

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