Mechano-optical transmittance and third order nonlinear optical properties exhibited by Au nanoparticles

Acceleration and velocity of Au nanoparticles suspended in ethanol were evaluated by considering optical transmittance experiments as a function of time. The evolution of the third order nonlinear optical characteristics of the sample was examined by a two-wave mixing technique at 532 nm wavelength with nanosecond pulses. The dynamical position and the nonlinear optical properties of the studied nanogold showed a strong dependence on nanoparticle size; besides an exponential behavior due to intermolecular interactions was estimated. A time-resolved mechano-optical effect was experimentally observed by a nanosecond optical Kerr gate configuration. Atomic Force Microscopy studies in a dielectric thin film sample prepared with the nanoparticles by a sol-gel processing route were conducted to determine the nanoparticles size distribution. Micrographic analysis pointed out that the explored nanoparticles size is between 65 and 155 nm with an average size of 98 nm. Potential applications for developing mechano-optical operations capable to modulate optical signals dependent on time were contemplated.