Temperature and Composition Dependence of Kinetics of Phase Separation in Solid Binary Mixtures

Abstract

We present results for the kinetics of phase separation in solid binary mixtures ($A_1+A_2$) from Monte Carlo simulations of the Ising model in two dimensions. The simulation results are understood via appropriate application of the finite-size scaling theory. At moderately high temperatures, for symmetric $(50:50)$ compositions of $A_1$ and $A_2$ particles the average size of the domains exhibit power-law growth with the exponent having the Lifshitz-Slyozov value of 1/3 from very early time. However, our analysis shows that for low enough temperatures, the growth exponent at early time is smaller than the Lifshitz-Slyozov value. For composition dependence, we find that at moderate temperature, even for extreme off-critical composition, curvature dependent correction to the growth law is weak which is counterintuitive in this case that gives rise to droplet morphology. This is however consistent with the recent understanding on curvature dependence of surface tension. Results from rather general studies on the finite-size effects with the variations of temperature and composition have also been presented.