Femtosecond measurement of third order optical nonlinearities in Bi

We present the measurement of the third-order nonlinearity of Bi2O3-B2O3-BaO glasses using the single Z-scan method with femtosecond laser pulses at 750-850 nm. Both third-order nonlinear refraction \gamma and two photon absorption coefficient \beta are investigated. The \gamma shows an increasing tendency with increasing BaO content, and the largest value is estimated to be 7.2×10-14 cm2/W, which is as large as those of chalcogen