Abstract

Transient NOPC is analyzed from the viewpoint of potential scattering. The probe, the nonlinear optical medium, and the conjugate fields are represented by appropriate wavepackets. Instead of considering the generation of a conjugate wave as a coherent sum of the diffracted fields from the gratings, the point of view here is that of resonant collision of a probe field wavepacket with that of the material medium. The coupling is provided by third-order nonlinear optical susceptibility. Transient NOPC is considered here as a three-wave resonant interaction process in which the middle envelope of the material medium is not significantly changed during the interaction as is usual in NOPC using four-wave mixing (FWM). The coupled probe-conjugate field equations are solved as a Zakharov-Shabat eigenvalue problem in the nonoverlapping wavepacket configuration and a general expression for the conjugate field at the FWM cell exit is obtained, which is then specialized for a constant coupling of finite extension. Finally, the inverse scattering transform methodology is used to investigate the time asymptotic behavior of the conjugate signal at the cell exit as well as the time evolution of the potential, which has received considerable attention lately.

© 1991 Optical Society of America