Preparation of high refractive index La2O3–TiO2 glass by aerodynamic levitation technique and effects of Bi2O3 substitution on its thermal and optical properties

La4Ti9O24 and Bi2O3-substituted La2O3–TiO2 glasses were prepared by aerodynamic levitation technique. The effect of Bi2O3 substitution on the thermal stability, refractive index and transmittance spectrum of the as-prepared samples were investigated. After Bi2O3 substitution, the stability of La2O3–TiO2–Bi2O3 glass decreased, but the Abbe number increased with glass refractive indices above 2.2 in visible region. The high refractive index can be attributed to the large oxygen packing densities and electronic polarizabilities of oxygen ions in the glasses.