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Ultrasensitive detection of weak resonances--application to optical frequency standards
Published
Author(s)
Jun Ye, L -. Ma, John L. Hall
Abstract
We present our latest results on the ultrasensitive molecular overtone spectroscopy using the cavity-enhanced frequency modulation (FM) technique. The principle of this technique makes use of a high-finesse external cavity to enhance the intrinsic resonance contrast, while an FM modulation approach provided shot-noise limited signal recovery. Working with a 1.064 υm Nd:YAG laser, we have obtained sub-Doppler overtone resonances of C2HD, C6d2^H2 and CO2 molecules. A detection sensitivity of 5x10-13 of integrated absoption (1x10-14/cm) over 1-s averaging time has been achieved. The resultant high signal-to-noise ratio of the weak resonance produces excellent laser frequency stabilization.
Citation
International Conference on Laser Spectroscopy
Pub Type
Journals
Keywords
FM spectroscopy, high-finesse cavity, molecular overtone spectroscopy, ultrasensitive detections
Citation
Ye, J.
, Ma, L.
and Hall, J.
(2008),
Ultrasensitive detection of weak resonances--application to optical frequency standards, International Conference on Laser Spectroscopy
(Accessed October 10, 2025)