Nonlinear Responses and Optical Limitation of Copper Nanoparticles by Z-Scan Method

Abstract

Recently, Copper particles in nano dimensions have been gaining attention. Because they have advanced features and potential applications in various fields. This work studies the nonlinear optical performance of copper nanoparticles. We utilized laser ablation to create copper nanoparticles. This in technique, a piece of copper in distilled water is irradiated using the laser beam. Laser ablation was done for 30 min. The optical nonlinearities are measured by means of the Z-scan technology. The open-aperture Z-scan experiments showed that Cu nanoparticles have strong nonlinear absorption. Through a closed aperture Z-scan experiment, we could analyze the nonlinear refraction of sample. We analyze the optical limiting effect of copper nanoparticles. A theoretical model is presented and shows that at high laser light intensity, nonlinear light scattering occurs. By analyzing the experimental data with the presented model, the values of optical nonlinearities of copper particles were found to be n2=0.8 x 10-19m2w-1, and y=1.46 x 10-13m/W respectively. Our work confirmed that Cu nanoparticles show outstanding nonlinear optical features, which can cause the development of nonlinear optics.