MEASUREMENT OF CW HF LASER RESONANT DEGENERATE 4-WAVE MIXING IN AN ABSORBING HF GAS

Continuous wave (cw) phase conjugation of a HF laser beam has been observed using resonant degenerate four-wave mixing in a HF gas absorption cell. A HF laser was operated in the P1(8) transition to provide total (forward plus backward) pump beam and probe beam intensities of about 400 and 30 W/cm2, respectively, in the cell. Conjugate reflectivities were measured as a function of HF pressure and frequency detuning from line center. Reflectivities of the order of 10-4 were measured at HF gas pressures of the order of 2 Torr when the laser frequency was tuned near line center.