Temperature dependence of domain growth

Monte Carlo simulations have been carried out to study the effect of temperature on the growth kinetics of a circular grain in two dimensions (2D) and a spherical grain in three dimensions (3D) for the Ising model. The domain radius shrinks as R2(t)=R20-αt, where R0 and R(t) are the initial and instantaneous radii, respectively. The slope α is strongly temperature dependent for T>0.6Tc in 2D and for T>0.2Tc in 3D, in contrast to earlier theories which neglect fluctuations. An analytical theory for d=2 which considers the thermal fluctuations which give rise to roughening of the domain walls agrees with the T dependence of the Monte Carlo data in this regime.