Designer 'Active' granular matter for probing the physics of non-equilibrium glass transitions

Abstract

Gaining microscopic insights into the true nature of the glass transition remains one of the most challenging problem in condensed matter physics [1]. Glasses are di cult to understand since they are mechanically rigid like crystals but at the same time have a disordered structure like that of a liquid. Glasses and other amorphous solids could be made of atoM.S., organic molecules, polymers, or assemblies of colloidal particles. Glass formation in various kinds of materials exhibit remarkably universal features. A large portion of this e ort in understanding the glass transition problem, however, has focused on systeM.S. that are in thermal equilibrium. The question address in this thesis is how the glass transition phenomenology changes if the system is driven by uctuations that do not have a thermal origin? In the last decade it has been realized that many of the phenomena associated with glassy dynamics are also observed in two prototypical non-equilibrium systeM.S. driven granular media [2{7] and active matter [8]. These systeM.S. are out of equilibrium as there is continuous input of energy at each particle level and detailed balance is violated. The term active matter encompasses a variety of di erent materials [8], ranging from living tissues to active colloidal particles to macroscopic granular matter driven by external forcing.