فهرست نشریات علمی دسترسی آزاد ایران

This work investigates the non-linear optical properties of thin films composed of an organic laser three-dye combination (Fluorescein, Eosin-Y and Rhodamine B) doped with PMMA polymer and incorporating (Ag, Cu, and SiO2) nanoparticles dissolved in chloroform solvent at room temperature, The thin films were prepared by drop-casting dye solutions at a concentration of 10-3 M. The absorption spectra were recorded in the (300-800) nm range. X-ray analysis was utilized to determine the structure and composition of materials. Where the(Mix+ PMMApolymer +Ag nanoparticles) exhibited the highest crystallinity. The AFM assay results for thin films after deposition of the polymer-based dye mixture and nanomaterial’s revealed that as the film thickness increased, the surface roughness and average diameter increased, thus increasing the linear absorbance, which in turn increased the nonlinear absorption coefficient. The nonlinear optical parameters, including the nonlinear absorption coefficient (β) and nonlinear refractive index (n₂), were measured using the open- and closed-aperture Z-scan technique. The open-aperture results confirmed that the saturable absorption was present in all thin films. Strong nonlinear optical responses were observed, with a linear dependence of the nonlinear refractive index on the nonlinear phase shift. The results suggest that the prepared films are suitable for use as an active laser medium and in optoelectronic application.