Dynamic effect of weak localization on the light scattering from random media using ultrafast laser technology

Abstract

Angle and time resolved experiments on the backscattering of light from model random media are presented. Weak localization was observed using 30-fs laser pulses, where this time scale is shorter than the scattering mean free time of the light in the random medium. This observation implies that the coherent peak is due to interference between the scattered light at the point of observation. The time resolved experiment directly shows that the light rays which undergo longer scattering paths contribute to the narrow coherent peak. A proper description of the temporal profile pulses scattered from random media requires the effect of weak localization to be taken into account.