Active fluids of Quincke microrotors
Petia Vlahovska, Northwestern

The electrically induced rotation of a sphere in an applied uniform DC field (Quincke effect) has been exploited to engineer self-propelled particles (Bricard et al, Nature (2013)), by converting rotational to translational motion when the particle is on a surface. In this talk, I will present our experiments showing how the Quincke rollers, previously studied mainly as active Brownian particles, can be designed to perform Run-and-Tumble-like locomotion mimicking bacteria such as E. coli. We achieve this by modulating the intensity and duration of the applied electric field. I will also discuss some novel collective dynamics levitating Quincke rotors: unlike the rollers, the “hovers” form crystals, chains and other dynamical structures