Research Article

Closed-Aperture Z-Scan Analysis for Nonlinear Media with Saturable Absorption and Simultaneous Third- and Fifth-Order Nonlinear Refraction

Figure 7

Closed-aperture Z-scan at = (a) 0.6, (b) 1.2, and (c) 1.8 GW/cm2 for the same film sample as that shown in Figure 5. Solid curves correspond to the least-squares fit of the theoretical formulae for the closed-aperture Z-scan with (red) and without (black) saturable absorption of a homogeneously broadened type. The best-fit values for and are (− )  cm2/GW and ( ) × 10−3 cm4/GW2, respectively. (d) as a function of input intensity . The solid line is the least-squares linear fit to the data.