Frequency stabilization of the sequence-band CO/sub 2/ laser using the 4.3-/spl mu/m fluorescence method

The saturated 1.3-/spl mu/m fluorescence stabilization method is applied to the 00/sup 0/2-[10/sup 0/1, 02/sup 0/1]/sub I,II/ sequence band CO/sub 2/ laser transitions. For this purpose, the 4.3-/spl mu/m fluorescence is observed using an external longitudinal CO/sub 2/ absorption cell heated to 300/spl deg/C. The dependence of the frequency stability upon the gas temperature and pressure in the cell as well as laser parameters have been carried out in absolute frequency scale with the help of a two-channel heterodyne system. Under optimal conditions, the standard deviation of the beat note frequency between sequence band and regular band lasers for 30 s averaging time is less than 20 kHz, and the long-term stability and reproducibility is achieved at about 10 kHz.<
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