CLASSICAL WAVE-PROPAGATION IN STRONGLY SCATTERING MEDIA

The transport of classical waves in strongly scattering media is inves tigated using ultrasonic techniques, allowing us to measure both the b allistic and scattered components of the wave field. We fmd that the b allistic propagation is dramatically slowed down by scattering resonan ces, although the group velocity remains well-defined. The propagation of the scattered waves is also strongly affected by resonant scatteri ng, and is shown to be well described by using the diffusion approxima tion. A model based on the generalized coherent potential approximatio n gives a quantitative explanation of the experimental data.