Third-order Nonlinear Optical Properties of Silver Quantum Dots Doped in Sodium Borosilicate Glass

Silver quantum dots doped in sodium borosilicate glass were synthesized through Sol-Gel method using tetraethyl orthosilicate(TEOS), boracic acid, metallic sodium as precursors. X-ray powder diffraction(XRD) analyses revealed that silver quantum dots were cubic crystalline phase; size and distribution of the quantum dots were measured by transmission electron microscope(TEM) as well as high-resolution transmission electron microscope(HRTEM). The results showed that spherical shape formed uniformly in the glass, and the size of these quantum dots ranged from 5 nm to 13 nm. Ultraviolet-visible(UV-Vis) absorption spectrometer obtained surface plasma resonance(SPR) absorption peaks as that of the Ag quantum dots at about 406 nm. Nonlinear optical properties of silver quantum dots doped glass were investigated by using Z-scan technique at the wavelength of 800 nm with femtosecond Ti: sapphire laser radiation. The values of nonlinear refraction index γ, nonlinear absorption coefficient β and the third-order nonlinear optical susceptibility χ(3)of the glass were estimated to be –1.72×10-17m2/W, 9.96×10-11m/W, 1.01×10-11esu,respectively.