Alladi Ramakrishnan Hall

Incomplete phase separations in scalar active matter

Rajesh Singh

DAMTP, Cambridge

Microphase separation is often observed in suspensions of spherical active particles. In such suspensions, the scalar concentration is the only order parameter, when there is no orientational order in the bulk. In this talk, I describe a scalar field theory to study active phase separation. A novel self-shearing instability, which interrupts the growth of droplets by splitting it, is derived by coupling the order parameter to fluid flow. We obtain the steady-states of the field theory in terms of effective mechanical (causing flow) and diffusive (causing Ostwald ripening) tensions.