Nonlinear optical susceptibilities χ(2) of nitridosilicate powders Original Research Article

Nitridosilicates are of interest as novel nonlinear materials due to their extraordinary chemical and thermal stability. Unfortunately, large nitridosilicate single crystals are presently not available for the investigation of their nonlinear optical properties. The first experiments are presented in which an averaged nonlinear susceptibility χ(2) for several nitridosilicates is studied by using two different powder techniques, the Kurtz Perry method and the SHEW method (Second Harmonic Wave generated by an Evanescent Wave). We observe nonlinearities of the new materials which are comparable to those of LiIO3. The highest averaged Meff=(χeff(2))2/4n2ωnω2 values found are ∼0.9 pm2/V2. The refractive indices of the materials are determined to be between n=2 and 3.