Highly nondegenerate cascaded four-wave mixing of femtosecond pulses: 2D simulation and experiment

This paper presents a numerical study of cascaded four-wave mixing of noncollinear femtosecond pulses with Gaussian profiles crossing in a ~200 mum thick fused silica slide. And in order to accurately reproduce the spatial and spectral features of CFWM and to account for geometrical phase matching via the interaction angle, a true two-dimensional approach is required. The proposed model considers nonlinear propagation of the pulse envelopes on a 2D plane and solves it using a multi-step method based on Pade approximants for non-paraxial propagation.