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arXiv · 2609.20371

Inferring interactions between active particles using harmonic traps

Arnaud Compagnie·Joscha Mecke·Ivo Buttinoni·Hartmut Löwen
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Abstract

Quantifying the interactions between active Janus particles remains a challenge that needs to be addressed to describe their collective behaviour. Inspired by a photonic force microscopy setup where two active Janus particles are confined in separate optical tweezers, we derive the steady-state probability distribution of each particle bearing signatures of the pair phoretic interaction, which can be generalised to a broader range of interactions. This approach allows us to infer interaction forces and torques from positional configurations without any knowledge of the particle orientations. Unraveling the distance-dependent interaction between active particles is essential to harnessing them as building blocks for advanced materials with dynamic properties.

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Arnaud Compagnie, Joscha Mecke, Ivo Buttinoni, Hartmut Löwen. 2026-09-17. Inferring interactions between active particles using harmonic traps. https://arxiv.org/abs/2609.20371

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