COHERENT BACKSCATTERING OF LIGHT IN A NEMATIC LIQUID-CRYSTAL

The first observation of coherent backscattering (CB) in an optically anisotropic, homogeneous (liquid crystal) medium with long-range diele ctric tensor fluctuations is reported. The results are compared with p revious CB experiments in heterogeneous, centrosymmetric, isotropic sc attering media and with theoretical predictions for isotropic, noncent rosymmetric media. Fundamental differences and analogies between these cases are observed and explained. Other liquid crystal phases of pote ntial interest in the localization of electromagnetic modes are introd uced briefly.