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arXiv · 2005.06811

Microscale Marangoni Surfers

Kilian Dietrich·Nick Jaensson·Ivo Buttinoni·Giorgio Volpe·Lucio Isa
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Abstract

We apply laser light to induce the asymmetric heating of Janus colloids adsorbed at water-oil interfaces and realize active micrometric "Marangoni surfers". The coupling of temperature and surfactant concentration gradients generates Marangoni stresses leading to self-propulsion. Particle velocities span four orders of magnitude, from microns/s to cm/s, depending on laser power and surfactant concentration. Experiments are rationalized by finite elements simulations, defining different propulsion regimes relative to the magnitude of the thermal and solutal Marangoni stress components.

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Kilian Dietrich, Nick Jaensson, Ivo Buttinoni, Giorgio Volpe, Lucio Isa. 2020-05-14. Microscale Marangoni Surfers. https://doi.org/10.1103/physrevlett.125.098001

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