Statistics of level spacing of geometric resonances in random binary composites.

We study the statistics of level spacing of geometric resonances in the disordered binary networks. For a definite concentration p within the interval [0.2,0.7], numerical calculations indicate that the unfolded level spacing distribution P(t) and level number variance Sigma(2)(L) have general features. It is also shown that the short-range fluctuation P(t) and long-range spectral correlation Sigma(2)(L) lie between the profiles of the Poisson ensemble and Gaussion orthogonal ensemble. At the percolation threshold p(c), crossover behavior of functions P(t) and Sigma(2)(L) is obtained, giving the finite size scaling of mean level spacing delta and mean level number n, which obey the scaling laws, delta=1.032L(-1.952) and n=0.911L(1.970).