Abstract

The use of Stark and Zeeman tuning methods in conjunction with fixed frequency mid- or far-infrared lasers has become widely accepted. In this paper, I wish to describe two new spectrometers designed to make use of the high sensitivity of these techniques. Both spectrometers feature intracavity absorption cells and are designed to operate in the 5–7 and 9–11.5-μm regions using semi-sealed-off CO or CO₂ laser oscillators. One apparatus, for laser magnetic resonance, is a modification of one described previously¹ which utilizes a 12-in. electromagnet with a homemade Hall-stabilized sweeping power supply. The major modification is the removal of all intracavity Brewster windows except for one to separate the laser gain cell from the free radical absorption cell. By removing the windows and their associated losses, the sensitivity is enhanced and operation is possible on weaker laser transitions. The performance of the spectrometer will be illustrated with spectra of CH₂, FO, and CI. The second apparatus is for the study by the laser Stark technique of Van der Waals molecules and follows the successful application of this technique in the far-infrared by Ray et al.²

© 1986 Optical Society of America