Abstract
We present a theoretical description of the ultrasensitive cavity-enhanced spectroscopic technique called noise-immune cavity-enhanced optical heterodyne molecular spectroscopy (NICE OHMS) for the case of transitions described by a Voigt line shape. The two levels of modulation used in NICE OHMS are treated with the standard theory for frequency modulation spectroscopy and a Fourier description of wavelength modulation spectroscopy. We compare predicted line shapes with experimental results for pressure-broadened transitions in molecular oxygen and show that our description can be used to determine the spectroscopic parameters. A key aspect of this research is the application of NICE OHMS to broad absorption features across a range of wavelengths, and etalon effects are shown to limit the detection sensitivity.
© 2004 Optical Society of America
Full Article | PDF ArticleMore Like This
Florian M. Schmidt, Aleksandra Foltynowicz, Weiguang Ma, and Ove Axner
J. Opt. Soc. Am. B 24(6) 1392-1405 (2007)
Weiguang Ma, Aleksandra Foltynowicz, and Ove Axner
J. Opt. Soc. Am. B 25(7) 1144-1155 (2008)
Aleksandra Foltynowicz, Weiguang Ma, Florian M. Schmidt, and Ove Axner
J. Opt. Soc. Am. B 25(7) 1156-1165 (2008)