Photoacoustic gas sensing employing fundamental and frequency-doubled radiation of a continuously tunable high-pressure CO2 laser |
| |
Authors: | A Romann MW Sigrist |
| |
Institution: | Swiss Federal Institute of Technology (ETH), Institute of Quantum Electronics, H?nggerberg, 8093 Zürich, Switzerland, CH
|
| |
Abstract: | We present the first photoacoustic spectrometer for gas sensing employing both the fundamental and the frequency-doubled radiation
of a continuously tunable high-pressure CO2 laser with room temperature operation. A quasi-phase-matched diffusion-bonded GaAs crystal is used in the system for second-harmonic
generation. A pulsed photoacoustic detection scheme with a non-resonant cell, equipped with an 80-microphone array, is employed.
The wide continuous tuning range in the fundamental (9.2–10.7 μm) and the frequency-doubled (4.6–5.35 μm) regimes, together
with the narrow linewidth of 540 MHz (0.018 cm-1) for the 10-μm region and of 1050 MHz (0.0315 cm-1) for the 5-μm region, allow the measurement of gas mixtures, individual species and isotope discrimination. This is illustrated
with measurements on NO and CO2. The measured isotope ratio 15
NO/14
NO=(3.58±0.55)×10-3 agrees well with the literature (3.700×10-3) and demonstrates the good selectivity of the system.
Received: 30 April 2002 / Revised version: 10 June 2002 / Published online: 2 September 2002
RID="*"
ID="*"Corresponding author. Fax: +41-1/633-1077, E-mail: sigrist@iqe.phys.ethz.ch |
| |
Keywords: | PACS: 42 55 Lt 42 62 F 42 65 Ky 42 68 Ca 94 10 Gb 07 07 Df |
本文献已被 SpringerLink 等数据库收录! |
|