Journal of Physics Condensed Matter
Dynamic structure factor of percolation clusters at criticality
Abdelali Rahmani, C Benoit, Gérard Poussigue
Abstract
The dynamic structure factor of very large percolating clusters (bond and site), in two dimensions and three dimensions are calculated using the spectral moments method. Interactions are represented by the scalar model. Numerical results are presented and interpreted in terms of scaling arguments given by Alexander, Courtens and Vacher (ACV) in 1993. Concerning the q lambda <<1 limit, our results confirm and supplement previous numerical work and are in agreement with the scaling behaviour theoretically deduced by ACV. Concerning the q lambda >>1 limit, we have shown that the dynamic structure factor complies with the very nice asymptotic behaviour g(q, omega )=q y H(q lambda ( omega )) where the scaling function H(x) is of power-law form x - tau ' in agreement with the theory. However, our results indicate a scaling behaviour with exponents that differ from those deduced by theory. The values obtained for tau ' are 1.20 for the two-dimensional bond and site percolating lattices, and 1.00 for the three-dimensional percolating lattices. Comparisons with previous simulations are reported.