Enhancement of phase conjugation in plasma

Abstract

We analyze optimal conditions for enhancement of phase conjugation (PC) in plasma. Optimal enhancement can be achieved by using degenerate four-wave mixing in flowing plasma at nearly sonic velocity or alternatively by using nearly degenerate four-wave mixing in nonflowing plasma. The parameters for optimal enhancement of PC by using nearly degenerate four-wave mixing in the laboratory are related to degenerate four-wave mixing in the flowing plasma by the transformation to the flowing-plasma frame of reference. In this approach, the appropriate optimal PC enhancement conditions are related to the Doppler shifts. The new general conditions for optimal enhancement should be applicable to neutral gases as well, owing to the similarity in the fundamental mechanism of the PC, which in plasma is based on the pondermotive force and in neutral gases is based on the electrostrictive force.