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arXiv · 2602.23327

Memory-induced active particle ratchets: Mean currents and large deviations

Venkata D. Pamulaparthy·Rosemary J. Harris
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Abstract

We analyse a continuous-time random walk model with stochastic reversals of direction. There is no external potential but the reorientation mechanism generates a non-zero current from asymmetry in the forward and backward waiting-time distributions (even when they have the same mean); the system can therefore be considered as a type of active particle ratchet. We derive an explicit expression for the mean ratchet current with exponentially distributed reorientation times and also develop a general renewal-theory framework to obtain the full large deviations, using this to comment on the possibility of dynamical phase transitions.

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Venkata D. Pamulaparthy, Rosemary J. Harris. 2026-02-26. Memory-induced active particle ratchets: Mean currents and large deviations. https://doi.org/10.1103/7w8f-5l87

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