Nonlinear all-optical light valves fabricated on mesoscopic Ti-, Si-substrates

Nonlinear optical properties are investigated in new composite materials. The investigated samples have been (i) a glass substrate covered by mesostructured (SiO2 or TiO2) film filled with the dye Rhodamine 6G, and (ii) a hybrid liquid crystal (LC) cell made on such mesostructured film. The nonlinear optical coefficients have been defined by two different techniques: the degenerate two-wave mixing in the regime of Raman-Nath self-diffraction, and the Z-scan method. The nonlinear optical absorption in the hybrid LC cell is strengthening under continuous laser radiation. The hybrid LC cell is perspective for applications in optical limiting and light-control-light LC valves.