New SMMW laser transitions optically pumped by a tunable CO2waveguide laser

Optical pumping of a submillimeter wave (SMMW) laser with a relatively compact RF-excited CW CO
2
laser is described. The increased frequency tunability of the waveguide pump laser has resulted in new low threshold SMMW emissions in C
2
H
2
F
2
, CDF
3
, and CD
2
F
2
by pumping into absorption lines which are beyond the tuning range of a conventional CO
2
laser. Frequency offsets and some assignments obtained with the aid of a tunable diode laser heterodyne spectrometer are reported.