International Journal of Optics and Photonics

en Nonlinear Optical Properties of Silver Nanoparticles Produced by Laser Ablation اپتیک غیر خطی Nonlinear Optics پژوهشي Research In this study, we investigated the production of silver nanoparticles by pulsed Nd: YAG laser ablation with λ=532nm in distilled water. The sodium citrate used to control the size of nanoparticles (Nps). The sample containing Ag NPs was characterized by linear absorption spectroscopy (UV-Visible spectroscopy) and transmission electron microscopy (TEM observation). The behavior of nonlinear optical properties of silver nanoparticles was studied using the Z-Scan method at two optimum numbers of the laser pulses and four optimum laser energy densities. In the Z-Scan method, the nonlinear thermal properties of Ag NPs were investigated under exposure to nanosecond laser pulse at λ=532nm. They were gained by fitting theoretical and experimental data. The values of the nonlinear refractive index (n2) and the nonlinear absorption coefficient (β ) were compared concerning to two optimum numbers and four optimum energy densities. The results of the nonlinear refractive index showed a negative value for each sample, this means that samples act as a divergent lens, and the thermal self-defocusing effect can be the main factor of nonlinear behavior. Following the comparison of two quantities, n2 and β , we found that the nonlinear refractive index increased when the number of laser pulses light increased. In addition, the nonlinear absorption coefficient decreased when the number of laser pulses light increased. As a result, the application of these Ag NPs for optical switching devices was investigated, which demonstrated that the large Ag NPs are applicable tools for optical switching devices. Laser ablation, Nonlinear Optical properties, Size of Silver nanoparticles, Z-scan method. 187 200 http://ijop.ir/browse.php?a_code=A-10-916-1&slc_lang=en&sid=1 Bita Azemoodeh afshar b.azmoodehafshar@urmia.ac.ir 10031947532846004676 10031947532846004676 No Physics Department, Faculty of Sciences, Urmia University, Urmia, Iran Akbar jafari a.jafari@urmia.ac.ir 10031947532846004677 10031947532846004677 No Physics Department, Faculty of Sciences, Urmia University, Urmia, Iran Rahim Naderali r.naderali@urmia.ac.ir 10031947532846004678 10031947532846004678 Yes Physics Department, Faculty of Sciences, Urmia University, Urmia, Iran Maqsood Golzan m.gilzan@urmia.ac.ir 10031947532846004679 10031947532846004679 No Physics Department, Faculty of Sciences, Urmia University, Urmia, Iran