FREQUENCY MEASUREMENTS OF OPTICALLY PUMPED FAR-INFRARED LASER LINES

In this work, we report the frequency measurements of optically pumped Far-Infrared (FIR) laser lines. We use the heterodyne technique of mi xing FIR laser radiation and microwave radiation on a Metal-Insulator- Metal (MIM) point contact tunnel diode, to determine the FIR laser fre quencies. The two FIR laser systems, consisting of CO2 waveguide pump lasers and Fabry-Perot FIR laser cavities, and MIM diode were develope d by us, To check the system, we have measured some FIR laser line fre quencies previously reported in the literature. An average fractional frequency reproducibility of +/-7 x 10(-7), between our measurements a nd the previous ones, permit us to use our system to measure five new FIR laser frequencies.