Non universal DLA and exact fractal dimensions

P. Ossadnik; C. -H. Lam; L. M. Sander

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arXiv · cond-mat/9402003

Non universal DLA and exact fractal dimensions

P. Ossadnik·C. -H. Lam·L. M. Sander

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Abstract

In analogy to recent results on non-universal roughening in surface growth [Lam and Sander, Phys. Rev. Lett. {\bf 69}, 3338 (1992)], we propose a variant of diffusion-limited aggregation ($DLA$) in which the radii of the particles are chosen from a power law distribution. For very broad distributions, the huge particles dominate and the fractal dimension is calculated exactly using a scaling theory. For narrower distributions, it crosses back to DLA. We simulated $1200$ clusters containing up to $200,000$ particles. The fractal dimensions obtained are in reasonable agreement with our theory.

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P. Ossadnik, C. -H. Lam, L. M. Sander. 1994-02-01. Non universal DLA and exact fractal dimensions. https://arxiv.org/abs/cond-mat/9402003

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