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arXiv · 2505.00141

Expanding Active Matter to the Third Dimension: Exploring Short and Long-Range Particle-Wall Interactions

Sandeep Ramteke·Jordan Dehmel·Touvia Miloh·Jarrod Schiffbauer·Alicia Boymelgreen
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Abstract

Most active colloid experiments are quasi-2D. Here a 3D density-matched solution of active particles propelled and aligned with an AC electric field uniquely facilitates measurement of short and long-range particle-wall interactions. Near-wall mobility is reduced by Stokes drag and local electric-field distortion. Long-range attractions concentrate particles at upper and lower walls at a ratio dependent on particle orientation and rate proportional to speed and confinement. This approach may be extended to other active systems to understand particle-wall interactions and non-equilibrium phenomena.

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Sandeep Ramteke, Jordan Dehmel, Touvia Miloh, Jarrod Schiffbauer, Alicia Boymelgreen. 2025-04-30. Expanding Active Matter to the Third Dimension: Exploring Short and Long-Range Particle-Wall Interactions. https://doi.org/10.1103/q9x6-wd7r

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