TY - JOUR
T1 - Subdiffusion and intermittent dynamic fluctuations in the aging regime of concentrated hard spheres
AU - al Masri, J.H.M.
AU - Berthier, L.
AU - Cipelletti, L.
PY - 2010
Y1 - 2010
N2 - We study the nonequilibrium aging dynamics in a system of quasihard spheres at large density by means of
computer simulations. We find that, after a sudden quench to large density, the relaxation time initially increases
exponentially with the age of the system. After a surprisingly large crossover time, the system enters
the asymptotic aging regime characterized by a nearly linear increase in the relaxation time with age. In this
aging regime, single-particle motion is strongly non-Fickian, with a mean-squared displacement increasing
subdiffusively, associated with broad non-Gaussian tails in the distribution of particle displacements. We find
that the system ages through temporally intermittent relaxation events, and a detailed finite-size analysis of
these collective dynamic fluctuations reveals that these events are not spanning the entire system, but remain
spatially localized.
AB - We study the nonequilibrium aging dynamics in a system of quasihard spheres at large density by means of
computer simulations. We find that, after a sudden quench to large density, the relaxation time initially increases
exponentially with the age of the system. After a surprisingly large crossover time, the system enters
the asymptotic aging regime characterized by a nearly linear increase in the relaxation time with age. In this
aging regime, single-particle motion is strongly non-Fickian, with a mean-squared displacement increasing
subdiffusively, associated with broad non-Gaussian tails in the distribution of particle displacements. We find
that the system ages through temporally intermittent relaxation events, and a detailed finite-size analysis of
these collective dynamic fluctuations reveals that these events are not spanning the entire system, but remain
spatially localized.
U2 - 10.1103/PhysRevE.82.031503
DO - 10.1103/PhysRevE.82.031503
M3 - Article
SN - 1539-3755
VL - 82
JO - Physical Review. E, Statistical, nonlinear, and soft matter physics
JF - Physical Review. E, Statistical, nonlinear, and soft matter physics
M1 - 031503
ER -