Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group

Enhancement of trace gas detection by integrating wavelength modulated spectra across multiple lines

Not Accessible

Your library or personal account may give you access

Abstract

We describe and demonstrate a technique that enhances the sensitivity of a spectrometer for trace gas detection by employing wavelength modulation spectroscopy (WMS) and integrating the absolute value of the recorded spectra across multiple lines of the species. The sensitivity is further enhanced by conducting WMS with large modulation depths. This technique is demonstrated using a continuously tunable external cavity CW quantum cascade laser to record the second harmonic wavelength modulated spectra of NO2 across the peak of the R-branch from 1629.5 to 1633.9cm1. By integrating the absolute value of the resulting spectra, the detection sensitivity of NO2 is improved by a factor of 40 compared to the sensitivity achieved using single-line WMS with the same apparatus. By using this technique, we achieve a sensitivity of approximately 6  parts in 109 (ppb) using a short-path cell (a 1m absorption cell with two passes).

© 2010 Optical Society of America

Full Article  |  PDF Article
More Like This
Enhanced sensitivity for the detection of trace gases using multiple line integrated absorption spectroscopy

Andreas Karpf and Gottipaty N. Rao
Appl. Opt. 48(27) 5061-5066 (2009)

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Figures (5)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Equations (15)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All Rights Reserved