Phase conjugation of radiation in an inverted medium of an electron-beam-controlled CO laser

An experimental investigation was made of the feasibility of phase conjugation by four-wave mixing in the active medium of an electron-beam-controlled CO laser when generating a backscattered wave in a loop system. The energy of a backscattered pulse was 0.3 J, representing nearly 10% of the pump energy at the entry to the amplifier. Theoretical calculations were made of the reflection coefficients of weak waves incident on gain gratings. This was done for all the transitions as a function of the angle of incidence. The strongest reflection was observed for the radiation propagating opposite to the pump waves.