Spectral characterization of /spl chi//sup (2)/ cascading phenomena

Summary form only given. The nonlinear phase distortion that arises from cascaded /spl chi//sup (2)/ processes in noncentrosymmetric crystals has recently received considerable attention. For many practical applications one needs to measure the amplitude of the effective nonlinear index of refraction n/sub 2/ associated with this cascaded process. We propose a simple spectral method which allows one to evidence and characterize the /spl chi//sup (2)/ cascading phenomena occurring during second harmonic or sum frequency generation.