New class of screened growth aggregates with a continuously tunable fractal dimension

A new family of fractals is investigated. The fractal dimension $D_f$ is found to be equal to a variable parameter of the model characterizing the strength of the screening. Thus we can make fractals with arbitrary $D_f$, and study anomalous diffusion as a function of $D_f$. Our data support a generalization we propose of the recent Aharony-Stauffer conjecture based on the spatial distribution of ‘‘growth sites’’ of a fractal.