Effects of nanoparticles size and concentration and laser power on nonlinear optical properties of Au and Au-CdSe nanocrystals

Au and Au-CdSe nanoparticles (NPs) have been synthesized by organometallic pyrolysis method. Nano-crystals (NCs) structure was confirmed using high resolution transmission electron microscope (HRTEM) and X-ray diffraction (XRD). Nonlinear optical absorption is investigated by Z-scan technique using nanosecond laser pulses of second harmonic Nd:YAG. Intensity-dependence of nonlinear absorption on both nano-size and concentrations is reported. These are interesting findings which can be used to fabricate optical limiting and optical switching devices from NPs and hybrid systems.