Technique for measuring time-dependent optical nonlinearities using continuous time-resolved Z-scan

Summary form only given. The role of nonlinear optical materials in high-speed applications such as optical switching, amplification, frequency conversion, and limiting has created a need for an efficient method of characterizing time-dependent nonlinear phenomena. By varying the time delay between pump and probe pulses, the Z-scan technique has been applied to map out the nonlinear time response. While this method is well suited for resolving fast subnanosecond effects, the iterative process is cumbersome for measuring slower phenomena. In contrast, a dual-beam (pulsed-pump, cw-probe) Z-scan technique (CWZ-scan) presented here can simultaneously measure both fast and slow nonlinear mechanisms contributing to the nonlinear refractive index by recording cw-probe transmission. This has been applied here to CdTe.