CELLULAR-AUTOMATON FOR THE ORDER-DISORDER TRANSITION

We propose a probabilistic cellular automaton model with a rule that i nterchanges neighboring atoms to simulate the diffusion driven dynamic s of binary alloys. In particular, we consider the ordering transition of two dimensional binary alloys on a square lattice by assuming anti ferromagnetic couplings and measure the energy, specific heat, and cor relation functions as functions of temperature. We perform damage spre ading simulations and tile phase space structure that emerges consists of a single paramagnetic thermodynamic state at high temperatures and a two-basin phase space at low temperatures. The results are compatib le with all order-disorder phase transition at a temperature close to the Onsager exact value.