(9d) Collective Dynamics of Polarizable Active Particles Under Confinement | AIChE

(9d) Collective Dynamics of Polarizable Active Particles Under Confinement


Gomez, J. D., Vanderbilt University
Gaillard, G., Vanderbilt Unversity
Strategies for controlling the movement and collective dynamics of synthetic active particles are critical to enable applications in reconfigurable materials, transport of cargoand drug delivery. Electromagnetic fields are a convenient tool to controlthe autonomous motion of active particles due to the ease with which important parameters such as amplitude, frequency and phase can be modified. In addition, the response to the field is strongly dependent on the physical properties of the colloids. In this talk, I will discuss an approach that enables controlof the active colloids based on theirpolarizability.In addition, we investigate the effectsof polarizabilityon the collective behavior of activeparticlesat different levels and types of confinement (only active particlesas well asmixtures of active/passive particles).Weobservedthat polarizability strongly influences thecollective dynamics. At high concentrationsand frequencies around 1 kHz, Janus particles(JPs)withlow polarizability show collective rotational motion that onlyemerges at high concentrations. Whenhighly polarizable JPs are embedded ina lattice of passive particles, JPseitherbehaveas an active intersticial, an active lattice atom or engage in orbital motion around passive particles. Our resultsindicate the rich collective behavior is the result of complex couplingbetween induceddipoles, induced flows and hydrodynamic interactions.