The influence of gamma irradiation on linear and nonlinear optical properties of magnesium oxide nanoparticles via Z-scan technique

Magnesium oxide nanoparticles produced by sol-gel method characterized by SEM and FTIR spectroscopy. The grain size of synthesized nanoparticles increases after irradiated gamma on the nanoparticles. The complex refractive index and dielectric coefficient were calculated by FTIR spectra of magnesium oxide nanoparticles with and without gamma irradiation effect. Furthermore, gamma irradiation caused the optical constants of magnesium oxide nanoparticles, the complex refractive index and dielectric function decreased. As a result, after gamma irradiation the transversal/longitudinal optical, TO/LO phonon frequencies shifted to blue/red frequencies, respectively. The nonlinear optical responses of magnesium oxide nanoparticles with and without gamma irradiation were investigated by Z-scan technique at 532 nm. The results revealed that the self-focusing effect of sample in closed aperture and two photon absorption effect in open aperture Z-scan data. Consequently, the results confirmed that the gamma irradiation improved the optical responses of magnesium oxide nanoparticles. Gamma irradiation created some defects on its structure and caused to intensify the nonlinearity responses of magnesium oxide nanoparticles.

Automated summary

Magnesium oxide nanoparticles prepared by sol-gel method were characterized by SEM and FTIR spectroscopy, and their grain size increased after gamma irradiation. The optical responses of magnesium oxide nanoparticles improved after gamma irradiation, although defects were created in its structure as a result. The FTIR spectra were used to calculate the complex refractive index and dielectric constant of the nanoparticles, showing a decrease in optical constants after gamma irradiation.