Large nonlinear optical response of polycrystalline Bi 3.25La0.75Ti3O12 ferroelectric thin films on quartz substrates

Abstract

We measure the nonlinear susceptibility of B3.25La 0.75Ti3O12 (BLT) thin films grown on quartz substrates using the Z-scan technique with picosecond laser pulses at a wavelength of 532 nm. The third-order nonlinear refractive index coefficient y and absorption coefficient γ of the BLT thin film are 3.1 × 10 -10 cm2/W and 3 × 10-5 cm/W, respectively, which are much larger than those of most ferroelectric films. The results show that the BLT thin films on quartz substrates are good candidate materials for applications in nonlinear optical devices. ©2007 Optical Society of America.