Sub-Doppler mid-infrared spectroscopy of molecular ions
نویسندگان
چکیده
The technique of velocity modulation spectroscopy has recently been combined with cavity enhancement and frequency modulation methods into a technique called noise-immune cavity-enhanced optical heterodyne velocity modulation spectroscopy (NICE-OHVMS). We have implemented NICE-OHVMS with a cw-optical parametric oscillator (OPO) tunable from 3.2 to 3.9 lm, and used it to record spectra of the R(1,0) and R(1,1) transitions of the m2 fundamental band of H3 . The high optical power and cavity enhancement enable saturation of rovibrational transitions, which allows for line center frequencies to be measured with a precision of 70 kHz. 2012 Elsevier B.V. All rights reserved.
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