Short wavelength operation of the CH3F Raman FIR laser

Using the isotopic species¹³CH₃F in the methyl-fluoride Raman laser, we have observed kilowatt-level laser pulses which can be tuned over a series of intervals that are centered on pure-rotational transitions in thev₃ ground state with initial-state J values between 35 and 43, inclusively. Taken together, these tuning intervals cover ∼35% of the spectrum between 142 and 174 μm. Several straightforward improvements in the experimental setup, including the use of isotopically purer¹³CH₃F, should enhance the spectral coverage in this region.