Monte Carlo simulation for diffusion limited surface directed phase separation

Surface directed phase separation with one phase B spin down (-1) preferred by the substrate has been studied using Glauber kinetics and spin exchange (Kawasaki exchange) model with semi-infinite free boundary condition. A computer simulation program has been developed for this purpose following metropolis algorithm and assuming conserved spin case with zero total magnetization. The temporal evolution of the patterns at k(B)T similar or equal to 0.6 eV below transition temperature T-c has been observed taking anti ferromagnetic interaction. Lattice size 200 x 100 has been taken with 50 : 50 concentrations of components A and B. The time evolution of patterns shows visible domain growth increasing with time. The phase separation takes place at first and then wetting process of phase B dominates at later stages. Phase A spin up (+1) dewets partially or completely from the substrate and phase B wets the surface partially or completely vice-versa. As the system moves towards equilibrium, the diffusion process slows down asymptotically.