Nonlinear optical properties of lanthanum titanate glasses prepared by levitation melting

Lanthanum titanate glasses (17 La2O3-83 TiO2) are fabricated via aerodynamic levitation melting. Nonlinear refraction and absorption were measured with the Z scan technique using ∼550 ps optical pulses at 532 nm wavelength with peak intensities in the range of 0.25–2.5 GW/cm2. The two-photon absorption coefficient (β) and the effective nonlinear refraction coefficient (n2eff) are found to be, respectively, 2.19 cm/GW and 152 × 10−16 cm2/W (85 × 10−13 esu). The Raman gain is measured to be 106 × 10−11 cm/W. The nonlinearity strength is found to be nearly 60 times larger in lanthanum titanate glasses relative to silica.