Active Colloid Guided Non-Equilibrium Assembly.

Electric field activated metal-dielectric Janus colloids exhibit many interesting properties such as self-propulsion and self-assembly. Previous works suggest that active colloids when mixed with passive particles can produce interesting self-assembled structures such as hexagonal closed pack clusters, long chain like structures etc. However, experimental studies focused on understanding the interplay between self-propulsion and interparticle interaction in tuning the nature of the steady-state are limited. In this talk, I will discuss our efforts in constructing a phase diagram of possible steady-states in active-passive mixtures wherein the particles behave as electric dipoles. In our experimental system, we find that by tuning the interaction between colloids via an external electric field, the assembly of the system evolves from compact closed-pack structures to elongated structures. We expect our studies will offer insights into non-equilibrium assembly and pathways to achieve synthetic active gel out of binary suspensions of active and passive colloids.