Stochastic migrations of Marangoni surfers between two lobes of a dumbbell-shaped confinement

Alakesh Upadhyaya; VS Akella

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arXiv · 2407.20140

Stochastic migrations of Marangoni surfers between two lobes of a dumbbell-shaped confinement

Alakesh Upadhyaya·VS Akella

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Abstract

We report an experimental investigation on the stochastic migration dynamics of Marangoni surfers (camphor-infused paper disks) between the two lobes of a dumbbell-shaped chamber. We characterize the migration dynamics using survival analysis for a given configuration with a unique disk count in each lobe. Qualitatively, all the configurations exhibit stretched exponential decay with time, ascribed to a disk s aging. A given configuration s stability decreases with increasing pairwise interactions. The most stable configuration is always the one with equal partitioning of disks between the lobes, i.e., exactly one-half of disks in each lobe for even-numbered systems but with one extra disk in either of the lobes for odd-numbered systems. Furthermore, we model a camphor disk as a Chiral Active Particle (CAP), as initially proposed by Cruz et al. and show that decreasing motility (or aging) indeed causes the stretched exponential behavior.

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Alakesh Upadhyaya, VS Akella. 2024-07-29. Stochastic migrations of Marangoni surfers between two lobes of a dumbbell-shaped confinement. https://arxiv.org/abs/2407.20140

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