Wavelength intensity correlation functions for transmitted waves through a slab: Numerical results

Abstract

We present numerical results for the intensity correlation function C(Δλ) (where Δλ is the change in the wavelength) for transmitted waves, through a slab of width L, in the weak disorder limit. Our numerical results show that the correlation function scales as C(Δλ$L^P$) where P→2 for L≫20l (l is the elastic mean free path) and is reduced to P≃1.6 for L≃6l. We provide an analytic calculation for P which is in agreement with the numerical results. We have also calculated $C_E$(Δλ), the electric-field–electric-field correlation function (for optical waves) and find that $C_E$(Δλ)≃C(Δλ) for Δλ${\lambda }_{1/2}$ (where Δ${\lambda }_{1/2}$ is the value of Δλ at the half width). For Δλ>Δ${\lambda }_{1/2}$, C(Δλ) falls off more slowly and both correlations show an oscillatory behavior which is shown to arise from the finiteness of the sample.