Enhancement of structural rearrangement in glassy systems under shear flow

F. Corberi, G. Gonnella, D. Suppa

Published 1999-11-29, updated 2001-02-21Version 2

We extend the analysis of the mean field schematic model recently introduced for the description of glass forming liquids to the case of a supercooled fluid subjected to a shear flow of rate $\gamma$. After quenching the system to a low temperature $T$, a slow glassy regime is observed before stationarity is achieved at the characteristic time $\tau_g$. $\tau_g$ is of the order of the usual equilibration time without shear $\tau_g^o$ for weak shear, $\gamma \tau_g ^o<1$. For larger shear, $\gamma \tau_g ^o>1$, local rearrangement of dense regions is instead enhanced by the flow, and $\tau_g \simeq 1/(T\gamma)$.