Low loss AlN (aluminum nitride) waveguide and AlN (aluminum nitride) waveguide CO/sub 2/ laser

A hollow dielectric waveguide using AlN (aluminum nitride) is tested to build a compact CO/sub 2/ laser that is expected to be used for ultra-high sensitivity/resolution measurement of carbon dioxide concentration in atmospheric air. The attenuation constant of an AlN waveguide having a 2/spl times/2 mm bore is estimated to be as low as 0.017 dB/m. Small bore AlN waveguide CO/sub 2/ lasers have been built and can be operated at a high gas pressure of 60 to 200 torr by DC- or RF-discharge excitation and deliver an output power of around 3 watts from an active volume as small as 2/spl times/2/spl times/70 mm/sup 3/. This verifies that AlN is a low-loss superior material, in the infrared region, to be used as a waveguide laser/absorption cell in which the discharging gas pressure can be kept high.