Breakdown of Scale Invariance in the Phase Ordering of Fractal Clusters
نویسندگان
چکیده
Numerical simulations with the Cahn-Hilliard equation show that coarsening of fractal clusters (FCs) is not a scale-invariant process. On the other hand, a typical coarsening length scale and interfacial area of the FC exhibit power laws in time, while the mass fractal dimension remains invariant. The initial value of the lower cutoff is a relevant length scale. A sharp-interface model is formulated that can follow the whole dynamics of a diffusion controlled growth, coarsening, fragmentation, and approach to equilibrium in a system with conserved order parameter. [S0031-9007(98)06180-8]
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