Crossover scaling of rough surfaces: effects of surface diffusion with threshold

Surface properties of a random deposition model in which the effects of surface diffusion with the threshold Delta h are taken into account are studies in 1+1 dimensions. The surface diffusion occurs only when the difference of the height between the nearest neighbours is more than the threshold Delta h. The scaling properties of the surface of the deposit are studied as a function of the threshold Delta h of surface diffusion. It is shown that a crossover phenomenon in the surface structure of the deposit occurs from the no diffusion region on small length scales to the surface diffusion region on large length scales. The exponent beta , which describes how the surface thickness grows with the height of the deposit (for an extremely large deposit), varies from 1/2 (for high thresholds) to 1/4 (for low thresholds). The crossover length h c from the random filling deposition to the random deposition with surface diffusion scales as Delta h 1.71 .