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arXiv · 2405.01506

Chirotactic response of microswimmers in fluids with odd viscosity

Yuto Hosaka·Michalis Chatzittofi·Ramin Golestanian·Andrej Vilfan
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Abstract

Odd viscosity is a property of chiral active fluids with broken time-reversal and parity symmetries. We show that the flow of such a fluid around a rotating axisymmetric body is exactly solvable and use this solution to determine the orientational dynamics of surface-driven microswimmers. Swimmers with a force-dipole moment exhibit precession around the axis of the odd viscosity. In addition, pushers show bimodal chirotaxis, i.e., alignment parallel or antiparallel to the axis, while pullers orbit in a plane perpendicular to it. A chiral swimmer that itself has a broken parity symmetry can exhibit unimodal chirotaxis and always align in the same direction.

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Yuto Hosaka, Michalis Chatzittofi, Ramin Golestanian, Andrej Vilfan. 2024-05-02. Chirotactic response of microswimmers in fluids with odd viscosity. https://doi.org/10.1103/physrevresearch.6.l032044

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