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arXiv · 2409.14558

Magnetotaxis in droplet microswimmers

Martin W. Wagner·Freek Domburg·Carsten Krüger·Jens Meyer·Jiaqi Zhang·Prashanth Ramesh·Corinna C. Maass
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Abstract

Magnetotaxis is a well known phenomenon in swimming microorganisms which sense magnetic fields e.g. by incorporating crystalline magnetosomes. In designing artificial active matter with tunable dynamics, external magnetic fields can provide a versatile method for guidance. Here, it is the question what material properties are necessary to elicit a significant response. In this working paper, we document in experiments on self-propelling nematic microdroplets that the weak diamagnetic torques exerted by a sub-Tesla magnetic field are already sufficient to significantly affect the dynamics of these swimmers. We find a rich and nontrivial variety of dynamic modes by varying droplet size, state of confinement and magnetic field strength.

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Martin W. Wagner, Freek Domburg, Carsten Krüger, Jens Meyer, Jiaqi Zhang, Prashanth Ramesh, Corinna C. Maass. 2024-09-22. Magnetotaxis in droplet microswimmers. https://arxiv.org/abs/2409.14558

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