Abstract
A twin optically-pumped far-infrared CH3OH laser has been constructed for use in plasma diagnostics. The antisymmetric doublet due to the Raman-type resonant two-photon transition is reproducibly observed at 118.8 μm. With the 118.8-μm line, it is obtained from the frequency separation of the anti-symmetric doublet that CH3OH absorption line center is 16±1 MHz higher than the pump 9.7-μm P(36) CO2 laser line center. It is shown that the Raman-type resonant two-photon transition is useful in order to get several-MHz phase modulation for the far-infrared laser interferometer. Some preliminary performances of this twin laser for the modulated interferometer are described.
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This work was carried out under the collaborating research program at the Institute of Plasma Physics, Nagoya University, Nagoya 464, Japan.
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Yamanaka, M., Takeda, Y., Tanigawa, S. et al. A twin optically-pumped far-infrared CH3OH laser for plasma diagnostics. Int J Infrared Milli Waves 1, 57–76 (1980). https://doi.org/10.1007/BF01007066
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DOI: https://doi.org/10.1007/BF01007066