Self-Polarizing Microswimmers in Active Density Waves.
An artificial microswimmer drifts in response to spatio-temporal modulations of an activating suspension medium. We consider two competing mechanisms capable of influencing its tactic response: angular fluctuations, which help it explore its surroundings and thus diffuse faster toward more active regions, and self-polarization, a mechanism inherent to self-propulsion, which tends to orient the swimmer's velocity parallel or antiparallel to the local activation gradients. We investigate, both numerically and analytically, the combined action of such two mechanisms. By determining their relative magnitude, we characterize the selective transport of artificial microswimmers in inhomogeneous activating media.
Institut für Physik, University of Augsburg, D-86159, Germany.
Alexander
A
Geiseler
Institut für Physik, University of Augsburg, D-86159, Germany.|Nanosystems Initiative Munich, Schellingstraße 4, D-80799 München, Germany.|Department of Physics, National University of Singapore, 117551 Singapore, Republic of Singapore.
Peter
P
Hänggi
Center for Phononics and Thermal Energy Science, School of Physics Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China.|Dipartimento di Fisica, Università di Camerino, I-62032 Camerino, Italy.
Fabio
F
Marchesoni