Tensor components of higher-order susceptibilities in a saturable absorber

Abstract

Higher-order nonlinearities may affect the performance of optical devices based on the third-order nonlinearity and may also be important in the characterization of nonlinear materials. A geometry of n-wave mixing to selectively probe each order of the nonlinearity was first proposed by Raj et al.,1 and its behavior was analyzed by us.2 We propose a theoretical model based on a holographic approach for all orders of the nonlinearities in a saturable absorber in stationary and transient regimes. Results of the theoretical calculation for the tensor components of the susceptibilities will be presented. We have performed experiments in the picosecond regime in which we used a frequency-doubled Nd:YAG mode-locked laser. We studied the fifth- and seventh-order nonlinearities for both isotropic and anisotropic materials. We used different beam polarization configurations to separate the components of the susceptibility tensors. In conclusion, we will discuss the importance of higher-order nonlinearities for complete characterization of nonlinear materials and the possibility of some devices using these nonlinearities.