Glass formation and third-order optical nonlinear characteristics of bismuthate glasses within Bi2O3–GeO2–TiO2 pseudo-ternary system

Glass-forming region of Bi2O3–GeO2–TiO2 (BGT) pseudo-ternary system was determined by using melt-quench method. A series of high transparent glass samples were selected and their structural characteristics were investigated by FT-IR and Raman spectra. By employing Z-scan and optical Kerr shutter techniques with femtosecond laser pulses as excitation source, third-order optical nonlinearities (TON) of the BGT glasses as well as the TON response time were investigated at wavelength of 800 nm. The ultrafast nonlinear response and high figure of merit suggest great potentials of BGT glasses in applications of all-optical switching or related optical devices.

► Glass-forming region of novel Bi2O3–GeO2–TiO2 system is determined. ► Increase of TiO2 or Bi2O3 content in BGT glasses promoted third-order optical nonlinearities. ► BGT glasses show ultrafast third-order nonlinear response time (<200 fs).