Transport equation for the time correlation function of scattered field in dynamic turbid media.
I derive a transport equation for the time correlation function in transmission and reflexion and inside a turbid medium. This equation goes beyond the diffusion approximation that is at the root of the well-established diffusing-wave spectroscopy technique. It takes into account all the transport regimes from ballistic to diffusive and the relaxation in direction at each scattering event. The derivation is based on a generalized form of the Bethe-Salpeter equation coupled to a generalized form of the scattering operator. The method presented can be easily adapted to compute the correlation function in systems with several time scales encountered, for example, in biology and polymer physics. The obtained equation is easily solvable numerically using a Monte Carlo scheme.
Pierrat
Romain
R
Laboratoire Kastler Brossel, Universite Pierre et Marie Curie, Paris, France. romain.pierrat@spectro.jussieu.fr