Light diffusion and coherent backscattering in nematic liquid crystals.

D.I. Kokorin

Thesis is devoted to simulation of multiple scattering of light in
nematic liquid crystals. We consider multiple scattering of light by
fluctuations of the director. The radiation transfer was simulated as a
random walk of photons in a medium. The transition from description in
form of contributions of separate scattering orders to the anisotropic
light diffusion has been studied in detail. The nonmonotonic dependence
of the diffusion coefficients of external magnetic field was found and
possible causes of nonmonotonic behavior were investigated.

The effect of coherent backscattering was simulated. The simulation
results are in better agreement with experimental data than the
results of approximate analytical calculations. The simulation
shows that a significant contribution to the shape of the peak intensity
comes from lower scattering orders, which can not be described by the
diffusion approximation.