Hyperuniform density fluctuations and diverging dynamic correlations in periodically driven colloidal suspensions

Elsen Tjhung (1) , Ludovic Berthier (1)

1 L2C - Laboratoire Charles Coulomb

The emergence of particle irreversibility in periodically driven colloidal suspensions has been interpreted as resulting either from a nonequilibrium phase transition to an absorbing state or from the chaotic nature of particle trajectories. Using a simple model of a driven suspension we show that a nonequilibrium phase transition is accompanied by hyperuniform static density fluctuations in the vicinity of the transition, where we also observe strong dynamic heterogeneities reminiscent of dynamics in glassy materials. We find that single particle dynamics becomes intermittent and strongly non-Fickian, and that collective dynamics becomes spatially correlated over diverging lengthscales. Our results suggest that the two theoretical scenarii can be experimentally discriminated using particle-resolved measurements of standard static and dynamic observables.

Domaines: Mécanique statistique [cond-mat.stat-mech]; Matière Molle [cond-mat.soft]

Elsen Tjhung, Ludovic Berthier. Hyperuniform density fluctuations and diverging dynamic correlations in periodically driven colloidal suspensions. Physical Review Letters, 2015, 114, pp.148301. ⟨10.1103/PhysRevLett.114.148301⟩. ⟨hal-01140762⟩