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arXiv · 2406.08289

Wobbling and Migrating Ferrofluid Droplets

Aaveg Aggarwal·Shih-Yuan Chen·Eleftherios Kirkinis·Mohammed Imran Khan·Bei Fan·Michelle M Driscoll·Monica Olvera de la Cruz
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Abstract

Active components incorporated in materials generate motion by inducing conformational changes in response to external fields. Magnetic fields are particularly interesting as they can actuate materials remotely. Millimeter-sized ferrofluid droplets placed on a solid surface, surrounded by an ambient gas phase, are shown here to migrate under a rotating magnetic field due to the periodic deformation of the liquid-gas interface. This interface wobbling leads to droplet migration with speeds that increase as the amplitude and frequency of the magnetic field increase. In addition to migrating in a controlled manner, we demonstrate the ability of magnetic droplets to clean surface impurities and transport cargo.

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Aaveg Aggarwal, Shih-Yuan Chen, Eleftherios Kirkinis, Mohammed Imran Khan, Bei Fan, Michelle M Driscoll, Monica Olvera de la Cruz. 2024-06-12. Wobbling and Migrating Ferrofluid Droplets. https://doi.org/10.1038/s42005-024-01871-8

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