The Artificial Pruning of the Irregular Surface of a Diffusion-Limited Aggregation and Its Effect on the Pattern Growth

Shu Matsuura and Nobuhisa Imai

Department of Physics, Faculty of Science, Nagoya University, Chikusa-ku, Nagoya 464, Japan

(Received September 1, 1989; Accepted December 12, 1989)

Keywords: Fractals, Diffusion-Limited Aggregation, Branch Growth Pattern, Pruning

Abstract. In this study, cluster formation due to diffusion-limited aggregation (DLA) has been simulated by introducing our new method, "circular pruning". The aim of this method is to take into consideration the surface entropy effect. This effect, although it has been not much considered in the usual basic DLA models, is thought to be of importance in pattern formation, since it must contribute to the formation of a symmetrical colony surface in the growth process. It has turned out through our simulation that cluster growth proceeded by repeating the "particle adsorption and surface pruning processes" is expressed by a fractal dimension D_f, the range of which is 1.7 D_f 2.0, controlled by the pruning parameter, l₀²/M₀, in Eq. (2).