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Title: Photoacoustic-based detector for infrared laser spectroscopy

Abstract

In this contribution, we present an alternative detector technology for use in direct absorption spectroscopy setups. Instead of a semiconductor based detector, we use the photoacoustic effect to gauge the light intensity. To this end, the target gas species is hermetically sealed under excess pressure inside a miniature cell along with a MEMS microphone. Optical access to the cell is provided by a quartz window. The approach is particularly suitable for tunable diode laser spectroscopy in the mid-infrared range, where numerous molecules exhibit large absorption cross sections. Moreover, a frequency standard is integrated into the method since the number density and pressure inside the cell are constant. We demonstrate that the information extracted by our method is at least equivalent to that achieved using a semiconductor-based photon detector. As exemplary and highly relevant target gas, we have performed direct spectroscopy of methane at the R3-line of the 2v{sub 3} band at 6046.95 cm{sup −1} using both detector technologies in parallel. The results may be transferred to other infrared-active transitions without loss of generality.

Authors:
;  [1]
  1. Department of Microsystems Engineering-IMTEK, Laboratory for Gas Sensors, University of Freiburg, Georges-Köhler-Allee 102, Freiburg 79110 (Germany)
Publication Date:
OSTI Identifier:
22594433
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 4; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ABSORPTION; ABSORPTION SPECTROSCOPY; CROSS SECTIONS; DENSITY; INFRARED SPECTROMETERS; LASER SPECTROSCOPY; LASERS; MEMS; METHANE; MOLECULES; PHOTOACOUSTIC EFFECT; PHOTOACOUSTIC SPECTROSCOPY; PHOTONS; QUARTZ; SEMICONDUCTOR MATERIALS

Citation Formats

Scholz, L., and Palzer, S., E-mail: stefan.palzer@imtek.uni-freiburg.de. Photoacoustic-based detector for infrared laser spectroscopy. United States: N. p., 2016. Web. doi:10.1063/1.4959886.
Scholz, L., & Palzer, S., E-mail: stefan.palzer@imtek.uni-freiburg.de. Photoacoustic-based detector for infrared laser spectroscopy. United States. doi:10.1063/1.4959886.
Scholz, L., and Palzer, S., E-mail: stefan.palzer@imtek.uni-freiburg.de. 2016. "Photoacoustic-based detector for infrared laser spectroscopy". United States. doi:10.1063/1.4959886.
@article{osti_22594433,
title = {Photoacoustic-based detector for infrared laser spectroscopy},
author = {Scholz, L. and Palzer, S., E-mail: stefan.palzer@imtek.uni-freiburg.de},
abstractNote = {In this contribution, we present an alternative detector technology for use in direct absorption spectroscopy setups. Instead of a semiconductor based detector, we use the photoacoustic effect to gauge the light intensity. To this end, the target gas species is hermetically sealed under excess pressure inside a miniature cell along with a MEMS microphone. Optical access to the cell is provided by a quartz window. The approach is particularly suitable for tunable diode laser spectroscopy in the mid-infrared range, where numerous molecules exhibit large absorption cross sections. Moreover, a frequency standard is integrated into the method since the number density and pressure inside the cell are constant. We demonstrate that the information extracted by our method is at least equivalent to that achieved using a semiconductor-based photon detector. As exemplary and highly relevant target gas, we have performed direct spectroscopy of methane at the R3-line of the 2v{sub 3} band at 6046.95 cm{sup −1} using both detector technologies in parallel. The results may be transferred to other infrared-active transitions without loss of generality.},
doi = {10.1063/1.4959886},
journal = {Applied Physics Letters},
number = 4,
volume = 109,
place = {United States},
year = 2016,
month = 7
}
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