Nonlinear Responses and Optical Limiting Behavior of Ag Nano-Particles

Ag nano-particles have been synthesized and the formation and microstructure of Ag particles, were monitored by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-Visible spectrum and z-scan technique. XRD pattern confirmed the cubic structure of the synthesized material. The UV-Visible spectrum of this material shows an absorption peak about 200 nm wavelengths. Optical limiting (OL) property of Ag nano-particles is studied. The nonlinear refractive indices of Ag nano-particles were defined by the z-scan technique using CW He-Ne laser (λ = 632.8 nm) at different incident intensities. The results reveal that the new complex exhibits strong nonlinear optics refraction effect such as self-focusing and the magnitude of n₂ was measured in order of 10⁻⁷ (cm²/W) with a negative sign.