Output Power Optimization and Gain and Saturation Irradiance Measurements on a RF-Pumped HCN Waveguide Laser.

A 1-m-long RF-pumped HCN waveguide laser is described. Output power optimizations were performed with mixtures of methane, nitrogen, and helium in the ratios 1:2:0, 1:1:0, 2:1:0, and 8:3:36. The variation of output power as a function of gas pressure, flow rate, waveguide wall temperature, and RF driving power was studied. A maximum output power of approximately 50 mW was obtained from the 337-mum line in the EH(11) cavity mode with the 1:1:0 mixture. Gain and saturation irradiance measurements were also performed on the same laser with an adjustable Michelson output coupler. The output power was measured as a function of the adjustment of the coupler, and a least-squares fit of a suitable laser model to the measured data was employed to furnish values for the small signal gain and saturation irradiance of the gain medium. Gain and saturation irradiance values were measured in this way for the above gas mixtures as a function of gas pressure, flow rate, and wall temperature, and the results were used to calculate the corresponding output powers. Reasonable agreement was found between these calculated powers and experimentally measured output powers. A quadratic variation of saturation irradiance with pressure is predicted by a simple theory and is also observed in the measured data.

[1]  S. Cooper,et al.  Plane-wave theory of a Michelson laser coupler with a dielectric slab beam splitter. , 1996, Applied optics.

[2]  S. Cooper.  A study of the indirect measurement of laser small signal gain and saturation irradiance and its application to an RF pumped HCN waveguide laser , 1994 .

[3]  E. M. Kuleshov,et al.  Waveguide HCN laser with controlled coupling , 1990 .

[4]  K. Kawahata,et al.  Suppression of laser noise in CW 337μm HCN lasers , 1989 .

[5]  P. Stimson,et al.  An experimental study of a CW optically pumped far infrared formic acid vapour laser , 1988 .

[6]  M. Kawamura,et al.  A capacitively coupled RF-excited CW-HCN laser , 1985, IEEE Journal of Quantum Electronics.

[7]  L. Whitbourn.  A 337μm density interferometer for the LT-4 tokamak , 1984 .

[8]  M. Makiuchi,et al.  A compact CW HCN gas laser with RF-excited discharge , 1983, IEEE Journal of Quantum Electronics.

[9]  M. Makiuchi,et al.  Effect of Oxygen on Compact CW-HCN Laser , 1982 .

[10]  D. T. Hodges,et al.  Calibration of power and energy meters for the far infrared/near millimeter wave spectral region , 1981 .

[11]  L W Casperson,et al.  Laser power calculations: sources of error. , 1980, Applied optics.

[12]  P. Belland,et al.  CW HCN laser gain in a hollow dielectric rectangular cross-section discharge tube , 1979 .

[13]  J. P. Crenn,et al.  Power scaling laws for cw HCN conventional Fabry-Perot lasers and comparison with cw HCN waveguide lasers. , 1979, Applied optics.

[14]  L. Whitbourn,et al.  Scaling laws for cw 337-microm HCN waveguide lasers. , 1976, Applied optics.

[15]  J. Vanderkooy,et al.  Design and characteristics of a 2 m continuous wave HCN laser , 1976 .

[16]  P. Belland,et al.  A compact cw HCN laser with high stability and power output , 1973 .

[17]  C. Bradley,et al.  A variable loss determination of HCN laser gain , 1973 .

[18]  O. Stafsudd,et al.  The CW gain characteristics of several gas mixtures at 337 microns. , 1969 .

[19]  D. Lide,et al.  ON THE EXPLANATION OF THE SO‐CALLED CN LASER , 1967 .

[20]  L. Frenkel,et al.  Absolute frequency measurement and spectroscopy of gas laser transitions in the far infrared. , 1967 .

[21]  E. Marcatili,et al.  Hollow metallic and dielectric waveguides for long distance optical transmission and lasers , 1964 .

[22]  H. Gebbie,et al.  A Stimulated Emission Source at 0.34 Millimetre Wave-length , 1964, Nature.