Aleksandr I. Ryasnyansky

Nonlinear optical properties of CdS and ZnS nanoparticles doped into zirconium oxide films

The nonlinear refraction and nonlinear absorption of ZrO2 thin films doped with CdS and ZnS nanoparticles and various metals were investigated using the Z-scan technique. The structural properties of these films (TEM, EDX) were compared with their optical and nonlinear optical characteristics. The values of nonlinear refractive index of these films were measured to be of the order of at a laser intensity of 9 ? 109?W?cm?2. Sign variations of ? of ZrO2:CdS(Cr) and ZrO2:ZnS(Mn) films due to fifth-order nonlinearities were observed and analysed using the intensity-dependent Z-scan studies of nonlinear optical parameters.

Theoretical investigation of the off-axis z-scan technique for nonlinear optical refraction measurement

The theoretical investigation of the off-axis z-scan technique for the measurement of nonlinear optical refraction in materials is presented. The normalized transmittance is calculated for different aperture radii and positions. The dependence of both the normalized transmittance amplitude (DeltaT(pv)) and the distance between maximum and minimum (Deltaz(pv)) on the aperture radius is analyzed. A condition for the applicability of the pinhole approximation is given.