Plasma diagnostic applications on the Text tokamak using a high power, twin frequency optically pumped far-infrared laser

A high-power, twin-frequency, optically-pumped, far-infrared (FIR) laser has been developed at UCLA for diagnostic application on the TEXT tokamak. The source is operated at 245 GHz (λ=1.22 mm) for heterodyne scattering measurements and 694 GHz (λ=432 μm) for high resolution interferometry. Future plans include a 30 channel interferometer/polarimeter operating at 694 GHz to accurately determine current profiles.