10. 6 micron parametric frequency converter. Final technical report, 1 Sep 1974--30 Oct 1976

Resonantly enhanced, single-sideband generation in a Stark tunable gas laser was demonstrated, both theoretically and experimentally, for the first time. The theory was developed first; it predicted the possibility of parametric mixing of infrared and microwave radiation in deuterated ammonia (/sup 14/NH/sub 2/D) gas, which would result in down converted single-sideband radiation at the difference frequency. Quantitative prediction of the nonlinear effect was made and is contained in the expression for the induced nonlinear coefficient. Pressure and Doppler broadening effects were accounted for in the coefficient. Successful experimental demonstration of resonantly enhanced, parametric single-sideband generation in /sup 14/NH/sub 2/D gas was made for the first time on this contract during October 1975. The P(20) line at 10.591 micrometers of the /sup 12/C/sup 16/O/sub 2/ laser and microwave at 4.023 GHz were mixed in a microwave-optical Stark cell, yielding a newly generated downconverted wave at 10.593 micrometers, or 944.061/cm. The dependences of the sideband signal on gas pressure, microwave frequency, applied dc field, and microwave power were measured and completely confirmed the theoretical predictions. A second experiment demonstrating resonantly enhanced parametric upconversion in Stark gas was also performed.