Persistence in Conserved Order Parameter Coarsening

Persistence in conserved order parameter coarsening is studied via computer simulation of the Cahn-Hilliard equation. Persistence $P(t_1, t_2)$ is defined as the fraction of the system that has not been traversed by a domain wall between times $t_1$ and $t_2$. We measure persistence as a function of volume fraction and establish that it decays according to a power law $P \sim t_2^{-\theta}$ for all volume fractions studied. We find that the persistence exponent $\theta$ depends on the volume fraction. Our results are then compared with an exact calculation applicable in the dilute limit.