Amplification of Stokes signals with phase conjugation by combined laser and SBS amplifiers

Various schemes for amplification of Stokes signals are investigated. Some new systems, such as an SBS amplifier in the transient amplification regime and a combined laser amplifie – SBS amplifier, are proposed and realised. Conditions are found under which amplification is accompanied by small distortions of the spatial structure of a signal. A two-pass system for small-signal amplification with phase conjugation is developed by using a PC mirror in the combined amplification system. The gains up to 10¹⁶ were obtained for the phase conjugation quality ~80%, the output energy ~1 J, and pulse duration ~30 ns.