An improved CO₂channel waveguide laser

Generation and Detection of Submillimetre (FIR) Radiation Using Optical Pumping in a Gas Laser System.

“…It is not trivial, however, to realize such a laser owing to the mismatches that occur between the emission lines in CO 2 and the absorptions in D 2 0, amounting to 0.32 GHz, 0.68 GHz and 1.5 GHz for R(22), R(12) and P(32) respectively. 1 No problem exists, of course, with a CO 2 TEA pump laser which can have an output several GHz wide due to pressure broadening, but for CW operation recourse must be made to capillary waveguide lasers which (unlike conventional devices) can operate at 100's of torr with consequent gain profiles typically 100's of MHz wide 2 . Waveguide lasers have been constructed in this laboratory from boron nitride (BN) 3 The combination of high thermal conductivity, low coefficient of expansion and ease of machining makes BN an ideal material with a better surface smoothness than that obtainable from beryllium oxide (BeO) or alimina (A1 2 0 3 ) . A typical laser consists of a 1.7 x 1.7 mm channel with 24 cm discharge length.…”

Novel CO2/N2O waveguide laser

“…We would like to point out that, while we have emphasized the use of alumina as a waveguide material, the same design concepts are applicable to materials such as beryllia and boron nitride, and would be especially attractive for the latter material since it cannot be sati~factorily epoxied. 6 Use of these materials becomes essential for very small bore lasers, for which the optical losses of alumina are too high. Furthermore, the use of swage-type fittings both as the discharge electrodes and as a conduit for flowing the lasing gases is also applicable to laser designs other than waveguide ones.…”