INFLUENCE OF INTERNAL-REFLECTION ON CORRELATION OF INTENSITY FLUCTUATION IN RANDOM-MEDIA

The correlation function of electromagnetic-intensity fluctuations is calculated in the diffusive regime in the presence of absorption using the Langevin approach. The results show that reflection of the bounda ry may cause drastic changes in the behavior of the correlation functi on. In the case of low absorption the spatial-correlation function und ergoes a crossover from a quadratic to a linear falloff with separatio n as the reflection increases. The autocorrelation function for a medi um with highly reflecting boundaries varies with frequency shift as (D ELTAomega)-1 instead of (DELTAomega)-1/2 for boundaries with low refle ction.