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arXiv · 2007.12466

Target search of active agents crossing high energy barriers

Luigi Zanovello·Michele Caraglio·Thomas Franosch·Pietro Faccioli
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Abstract

Target search by active agents in rugged energy landscapes has remained a challenge because standard enhanced sampling methods do not apply to irreversible dynamics. We overcome this non-equilibrium rare-event problem by developing an algorithm generalizing transition-path sampling to active Brownian dynamics. This method is exemplified and benchmarked for a paradigmatic two-dimensional potential with a high barrier. We find that even in such a simple landscape the structure and kinetics of the ensemble of transition paths change drastically in the presence of activity. Indeed, active Brownian particles reach the target more frequently than passive Brownian particles, following longer and counterintuitive search patterns.

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Luigi Zanovello, Michele Caraglio, Thomas Franosch, Pietro Faccioli. 2020-07-24. Target search of active agents crossing high energy barriers. https://doi.org/10.1103/physrevlett.126.018001

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