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Updated: May 27, 2026

Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
Noise immune cavity enhanced optical heterodyne velocity modulation spectroscopy
Brian M Siller1, Michael W Porambo, Andrew A Mills
1Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
Abstract:
The novel technique of cavity enhanced velocity modulation spectroscopy has recently been demonstrated as the first general absorption technique that allows for sub-Doppler spectroscopy of molecular ions while retaining ion-neutral discrimination. The previous experimental setup has been further improved with the addition of heterodyne detection in a NICE-OHMS setup. This improves the sensitivity by a factor of 50 while retaining sub-Doppler resolution and ion-neutral discrimination. Calibration was done with an optical frequency comb, and line centers for several N(2)(+) lines have been determined to within an accuracy of 300 kHz.
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