Iraqi Journal of Laser

In the present work, a z-scan technique was used to study the nonlinear optical properties, represented by the nonlinear refractive indexand nonlinear absorption coefficientsofnanoparticlescadmium sulfide thin film. The sample was prepared by the chemical bath deposition method.Several testing were done including, x-ray, transmission and thicknessofthinfilm.z-Scanexperiment was performed attwo wavelengths (1064 nm and 532 nm)and different energies. The results showed the effect of self-focusing in the material at higher intensities,whichevaluatedn2to be (0.11-0.16) cm2/GW. The effect of two-photon absorption was studied, which evaluated β to be (24-106) cm/GW. In addition, the optical limiting behavior has been studied. The results confirmed the capability of the sample to be used as optical limiter device

The main purpose of this work is the construction of an optical parametric amplifier(OPA)to generate a629nm pulsed laser. KTP nonlinear crystals were used for both parametric oscillation and amplification. A singly resonant parametric oscillator (OPO) is constructed to generate a signal of 1.54 μm and idler of 3.4 μm when the OPO system is pumped by 1.064 μm Q –switched Nd: YAG laser. The signal was then mixed with the pumping beam in OPA system to form the wanted wavelength. The obtained optical conversion efficiency was 60%.

Incident laser power and concentration effects on fluorescence emission from DCM dye in PMMA polymer have been investigated. Different concentrations of the dye were used. It was found that the fluorescence intensity increased with increasing of the concentration of the dye, with a red shift. In addition, it was found that the fluorescence intensity increased with the increase of the incident laser powerI0.