Nonlinear Optical Properties of Zinc Oxide Nanoparticle Colloids Prepared by Pulsed Laser Ablation in Distilled Water.

The nonlinear optical properties of zinc oxide nanoparticles (ZnONPs) in distilled water were measured using a femtosecond laser and the Z-scan technique. The ZnONPs colloids were created by the ablation of zinc bulk in distilled water with a 532 nm Nd: YAG laser. Transmission electron microscopy, an ultraviolet-visible spectrophotometer, and atomic absorption spectrophotometry were used to determine the size, shape, absorption spectra, and concentration of the ZnONPs colloids.

Design of an optical trap for storing femtosecond laser pulses.

An optical trap for storing femtosecond laser pulses to enhance the interaction effectiveness with optically thin targets is being proposed and investigated. Presently, we studied the trapping of 10-200 fs laser pulses of wavelength 800 nm, 1 μJ energy per pulse, and 10 Hz repetition rate. To compensate the optical losses in the trap, a Ti: Sapphire crystal as an amplifying medium is being considered, which should be synchronously pumped by the second harmonic of the Nd: YAG laser.

A linear optical trap with active medium for experiments with high power laser pulses.

A linear optical trap for circulating high power laser pulses and tuning these pulses to high repetition frequency of several tens of MHz has been developed. A ns excimer pumped dye laser pulse has been injected with help of a Wollaston prism and a synchronized Pockels cell into an optical trap formed by two highly reflecting mirrors in a linear configuration. The test was done at λ = 580 nm, but the optical trap can be used without limitations in a broad band of optical wavelengths (400-700 nm).