TIME-DOMAIN DEPOLARIZATION OF WAVES RETROREFLECTED FROM DENSE COLLOIDAL MEDIA

We report on depolarization measurements of femtosecond pulses retrore flected from dense suspensions of silica microspheres with solid loads increasing from 5% to 54%. Backscattered pulse shapes compare well wi th predictions of the diffusion theory for all volume fractions, and t he inferred values of the transport mean free path agree with independ ent measurements of enhanced backscattering. polarization decays expon entially with temporal rates that scale with the solid load. all solid loads, depolarization sets in for path lengths longer than approximat ely five transport mean free paths. (C) 1991 Optical Society of Americ a.