Abstract
Sensitive photoacoustic detection of ammonia with near-infrared diode lasers (1.53 µm) and a novel differential acoustic resonator is described; a sensitivity of 0.2 parts per million volume (signal-to-noise ratio = 1) is attained. To eliminate adsorption-desorption processes of the polar NH3 molecules, a relatively high gas flow of 300 SCCM was used for the ammonia-nitrogen mixture. The results are compared with recent ammonia measurements with a NIR diode and absorption spectroscopy used for detection and photoacoustic experiments performed with an infrared quantum-cascade laser. The performance of the much simpler and more compact setup introduced here was comparable with these previous state-of-the-art measurements.
© 2002 Optical Society of America
Full Article | PDF ArticleMore Like This
Milton B. Filho, Marcelo G. da Silva, Marcelo S. Sthel, Delson U. Schramm, Helion Vargas, Andras Miklós, and Peter Hess
Appl. Opt. 45(20) 4966-4971 (2006)
Anatoliy A. Kosterev and Frank K. Tittel
Appl. Opt. 43(33) 6213-6217 (2004)
Andreas Schmohl, Andras Miklos, and Peter Hess
Appl. Opt. 40(15) 2571-2578 (2001)