Simultaneous tunable raman and fixed frequency oscillation of a CH3F FIR laser

Experimental observation of simultaneous oscillation at the Raman frequency and a cascade frequency in a broadly tunable
¹³
CH
3
F far-infrared laser is reported. Oscillation on both components persists over the full 25 GHz separation between the
v_{3}R(36)
and
R(37)
lines. This observation is in marked contrast to the behavior of the tunable
¹²
CH
3
F FIR laser which produces only the Raman frequency when it is optically pumped at lower
J
values in the same branch. A marked qualitative difference in the large-scale emission spectra for the two lasers is also discussed.