Transmission of mobility via cooperative mechanisms in soft active matter

Abstract

When supercooled, liquids viscosity increases dramatically as the glass transition temperature is approached. While the physical origin of this behavior is still not understood, it is now well established that the addition of a few activated particles is able to reverse that increase in viscosity. Here we further raise the question of a limit in that fluidization process and of the differences between the fluidized liquid and its viscous counterpart. Results show that a few percent active molecules are enough to trigger a phase transition leading to diffusion coefficients typical of liquids while the medium retains cooperative properties of the viscous phase. The similarity between cooperative properties of the active and non active molecules suggests that the mobility of active molecules is transmitted to inactive ones via the medium cooperative mechanisms, a result in agreement with facilitation theories. This result is then confirmed by the compared behavior of the distinct van hove correlation functions of most mobile active and non active molecules. Interestingly enough, in our simulations the cooperative mechanisms are not induced or related to a decrease of the excitation concentration.

13 Figures

References in corpus (19)

• Novel type of phase transition in a system of self-driven particles
• Self-motile colloidal particles: from directed propulsion to random walk
• Physics of Microswimmers - Single Particle Motion and Collective Behavior
• Glassy dynamics of kinetically constrained models
• Pressure and Phase Equilibria in Interacting Active Brownian Spheres
• A self-propelled particle in an external potential: is there an effective temperature?
• Perspective: Nonequilibrium glassy dynamics in dense systems of active particles
• How active forces influence nonequilibrium glass transitions
• Calorimetric glass transition explained by hierarchical dynamic facilitation
• Active matter: quantifying the departure from equilibrium
• Dynamical facilitation governs glassy dynamics in suspensions of colloidal ellipsoids
• A simple diatomic potential that prevents crystallization in supercooled liquids simulations
• How does the motion of the surrounding molecules depend on the shape of a folding molecular motor ?
• Induced cooperative motions in a medium driven at the nanoscale: Searching for an optimum excitation period
• A kinetic-Monte Carlo perspective on active matter
• Folding time dependence of the motions of a molecular motor diluted inside an amorphous medium
• A toy model mimicking cage effect, structural fluctuations and kinetic constraints in supercooled liquids
• Simulations of supercooled water under passive or active stimuli
• Comparison of time reversal symmetric and asymmetric nano-swimmers oriented with an electric field in soft matter