Nonlinear properties of phototropic media on the basis of Cu_xSe nanoparticles in quartz glass

Energy and kinetic characteristics of theinduced transparency in quartz sol-gel glasses containing copper selenide nanoparticles of different stoichiometry are studied. The dependence of the nonlinear optical properties of the glass samples on the chemical composition of copper selenide particles, which gives rise to an additional absorption band in the near-infrared region and determines its spectral position, is established. It is found that the time of relaxation of the induced transparency increases and the peak absorption cross section decreases as the absorption maximum shifts to the low-energy spectral region.