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arXiv · 2509.20005

Living droplets with mesoscale swimmers

L. Malik·N. Sharadhi·C. Prêcheur Llarena·M. Lamminmäki·R. A. Lara·V. Jokinen·M. Lisicki·M. Backholm
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Abstract

We study the activity of 'living' droplets, which confine tens of swimming meso-organisms in 3D using a superhydrophobic substrate. With few swimmers, the droplet oscillates at its inherent resonant frequency. We observe deviations from this classical regime as the level of confinement or crowding increases and develop scaling law models to successfully describe our results. We report a difference in swimming kinematics in crowded 3D environments compared to quasi-2D. Our work reveals mechanisms for bio-inspired droplet actuation with implications for mesoscale robotics, fluidics, and sensing.

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L. Malik, N. Sharadhi, C. Prêcheur Llarena, M. Lamminmäki, R. A. Lara, V. Jokinen, M. Lisicki, M. Backholm. 2025-09-24. Living droplets with mesoscale swimmers. https://arxiv.org/abs/2509.20005

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