Third-order optical nonlinear characterizations of Bi2O3-B2O3-TiO2 ternary glasses

Third-order optical nonlinear characterizations of glasses in Bi2O3-B2O3-TiO2 ternary system were investigated using femto-second Z-scan method at 800 nm. Results show that third-order optical nonlinearities are influenced by TiO2 concentration, the largest value of nonlinear refraction gamma obtained is 8.85 x 10(-14) cm(2)/W. Further. the hyperpolarizability alpha((3)) of Bi-O-Ti4+ units which is considered to be main contribution to the large third-order nonlinearity is estimated to be 1.32 x 10(-33) esu cm(3)/unit. Additionally, enhancement of two-photon absorption process near 0.73E(opg) is observed. Crown Copyright (C) 2009 Published by Elsevier B.V. All rights reserved.