Commutative spatial and time symmetry of degenerate four-wave mixing measurements

The spatial and temporal configuration of a degenerate four-wave mixing (DF WM) experiment have been analyzed. Numerical calculations and experiments s how the clear dependence of the experimental signal value on the wave vecto r geometry. A commutative time symmetry method was applied to analyze data from DFWM measurements. The method permits the direct formulation of symmet ry transformation rules that can be used to analyze the temporal shape of t he diffracted pulse. This time symmetry approach was used to describe DFWM measurements on two third-order nonlinear materials, CS2 and polyacetylene thin films. The approach was used to analyze the slow decay temporal compon ent region for DFWM experiments. (C) 1999 optical Society of America [S0740 -3224(99)01005-X].