摘要: Although there has been a high level of interest in nonlinear optical effects for more than 20 years now, most the work this field concentrated on development noncentrosymmetric inorganic compounds such as LiNbO3 and analogues potassium dihydrogen phosphate (KDP). Many these crystals have commercialized form single-crystal frequency convertors, electro-optic modulators, recently simple waveguide couplers switches. Since about 1975 increasing organic with properties potential alternatives to inorganics mentioned above (Williams, 1983, 1984; Chemla Zyss, 1986). Much second-order properties, although third-order also described.