Model for in-coupling of etalons into signal strengths extracted from spectral line shape fitting and methodology for predicting the optimum scanning range: demonstration of Doppler-broadened, noise-immune, cavity-enhanced optical heterodyne molecular spectroscopy down to 9 × 10−14 cm−1
2015 (English)In: Journal of the Optical Society of America. B, Optical physics, ISSN 0740-3224, E-ISSN 1520-8540, Vol. 32, no 10, 2104-2114 p.Article in journal (Refereed) Published
Expressions for the in-coupling of white noise and etalons into fitted signal strengths are derived. These show that the amount of noise picked up is affected by the scanning range. A methodology for finding the optimum scanning range from a single set of measurements has been developed. This was used to estimate the optimum conditions of a noise-immune, cavity-enhanced optical heterodyne molecular spectroscopy (NICE-OHMS) setup. The methodology was validated by measurements. This resulted in a spectral noise equivalent absorption per unit length of 2.6 × 10−13 cm−1 Hz−1∕2 and a minimum Allan deviation of 9 × 10−14 cm−1 at 30 s, which are, to our knowledge, the lowest reported for Doppler-broadened NICE-OHMS
Place, publisher, year, edition, pages
Optical Society of America, 2015. Vol. 32, no 10, 2104-2114 p.
Absorption, Spectroscopy - heterodyne, Spectroscopy - modulation, Spectroscopy - molecular
Atom and Molecular Physics and Optics
IdentifiersURN: urn:nbn:se:umu:diva-110081DOI: 10.1364/JOSAB.32.002104ISI: 000367235700012OAI: oai:DiVA.org:umu-110081DiVA: diva2:861080