Nonlinear Optical Properties of Silver Composited Ge-In-S-CsI Chalcogenide Glasses

In this study,the Ag doped 70GeS2-20In2S3-10CsI chalcogenide glasses were synthesized by vacuumed melting-quenching technique.The third nonlinear optical properties were studied using Z-Scan technique at 800 nm.After being introduced Ag into the glass,both the linear and nonlinear refraction index γ increased from 2.204 to 2.2087 and from 23.3×10-18 to 30.5×10-18 m2/W,respectively.Besides,the nonlinear response time increased from 70 fs to 79 fs.The further heat treatment also enhanced the nonlinear refraction index up to 44.3×10-18 m2/W,2 folds higher than that of As2Se3.Meanwhile,the nonlinear absorption coefficient β decreased because the bandgap decreased with the thermal heat treatment.However,the highest figure of merit(FOM) is 3.3,which is enough for the nonlinear optics.Large nonlinear refraction index,high FOM,and fast response time ensured that the Ag-composited chalcogenide glass and glass ceramics can find applications in nonlinear optics.