NO trace gas sensor based on quartz-enhanced photoacoustic spectroscopy and external cavity quantum cascade laser

• DOI: 10.1007/s00340-010-3984-z
• Publication Date: 2010-03-16T06:33:45Z
• Authors: V. Spagnolo; A. A. Kosterev; L. Dong; R. Lewicki; F. K. Tittel
• Keywords: Quantum cascade laser; Trace gas; Photoacoustic Spectroscopy; SIGNAL (programming language); Photoacoustic effect

A gas sensor based on quartz-enhanced photoa- coustic detection and an external cavity quantum cascade laser was realized and characterized for trace nitric ox- ide monitoring using the NO R(6.5) absorption doublet at 1900.075 cm −1 . Signal and noise dependence on gas pressure were studied to optimize sensor performance. The NO concentration resulting in a noise-equivalent signal was found to be 15 parts per billion by volume, with 100 mW optical excitation power and a data acquisition time of 5 s.