Synthesis and nonlinear optical responses of Ag: ZnO core: shell nanoparticles induced by Z-scan technique

The objective of the scientific study was the synthesis; structural, morphological and measurement of the nonlinear optical characteristics of silver core and zinc oxide shell nanoparticles by the z scan technique. The silver core-zinc oxide shell nanoparticles were produced via laser with a size of nanoparticles between 21 and 38 nm with an average size of 29 nm and a size of silver nanoparticles with a range (27-42 nm) and an average size of 36 nm, while a size of zinc oxide nanoparticles had a range of 24 to 40 nm with an average size of 31 nm to measure the effect of nonlinear optical properties. The TEM and FE -SEM images displayed that an average diameter for the silver core- zinc oxide shell nano particles generated via the laser wavelength 1064-nm is smaller than the diameters of pure materials. UV-vis analyses revealed that the absorption peaks of silver nanoparticles and zinc oxide nanoparticles were located at 410 nm, 337 nm respectively. The absorption peaks of core-shell nanoparticles were located at 342 nm and 424 nm. The Z- scan method was used to characterize nanoparticles' nonlinear optical characteristics, specifically the nonlinear refractive index (n2), nonlinear absorption coefficients (beta), and core-shell nanothin films. The Z-scan experiment was conducted with a 1064 nm as a pumping source. The final data results demonstrated nonlinear refractive index increases with core-shell nanoparticles. Leading to an evaluation of n2 as (-0.32211, -0.3351, and - 0.3510) cm2/GW for silver, zinc oxide nanoparticles, and core-shell nanoparticles. The study investigated the nonlinear absorption coefficient beta, for samples, which demonstrated the increase in the value of beta, for core-shell nanoparticles (49 x 106) cm/GW. The results validated the sample's capacity to function as an optical limiter device.