Z-scan: A Simple Technique for Determination of Third-order Optical Nonlinearity

Z-scan is a simple experimental technique to measure intensity dependent nonlinear susceptibilities of third-order nonlinear optical materials. This technique is used to measure the sign and magnitude of both real and imaginary part of the third order nonlinear susceptibility (chi((3))) of nonlinear optical materials. In this paper, we investigate third-order nonlinear optical properties of Ag-polymer composite film by using single beam z-scan technique with Q-switched, frequency doubled Nd: YAG laser (lambda=532 nm) at 5 us pulse. The values of nonlinear absorption coefficient(beta), nonlinear refractive index (n(2)) and third-order nonlinear optical susceptibility (chi((3))) of pennethylazine were found to be 9.64 x 10(-7) cm /W, 8.55 x 10(-12) cm(2)/W and 5.48x 10(-10) esu, respectively.