J. S. Oliveira Filho, T. J. Oliveira, J. A. Redinz
We introduce a new class of growth models, with a surface restructuring mechanism in which impinging "hot" atoms may dislodge suspended particles (deposited following the ballistic deposition rule), previously aggregated on the same column in the deposit. The flux of these "hot" particles is controlled through a probability p. These systems present a crossover, for small values of p, from random to correlated (KPZ) growth of surface roughness, which is studied through scaling arguments and Monte Carlo simulations on one- and two-dimensional substrates. We show that the characteristic time of crossover t_{\times} scales with p according to t_{\times} \sim p^{-y} with y=(n+1) and that the interface width at saturation W_{sat} scales as W_{sat} \sim p^{-\delta} with \delta=(n+1)/2, where n is either the maximal number of bonds breaked or of suspended particles that may be dislodged. Thus, the exponents y=1 and \delta=1/2 or y=2 and \delta=1 found in all previous works, are not universal. Using scaling arguments, we show that the bulk porosity P of the deposits scales as P \sim p^{y-\delta} for small values of p. This general scaling relation explains previous results present in literature and is confirmed by our numerical simulations.
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http://arxiv.org/abs/1208.1547
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