Monitoring of Gaseous Pollutants by Tunable Diode Lasers

The 3rd International Symposium on Monitoring of Gaseous Pollutants by Tunable Diode th Lasers, held at the Fraunhofer Institute in Freiburg on October 17th and 18 , continued a tradition, established by the two preceeding meetings held at the same location, in 1986 and 1988. The steadily increasing number of participants and contributions emphasizes the need for such a meeting, which is unique in Europe and appreciated abroad. This third symposium in particular, was specially marked by the presence of the former Eastern Block Countries, with a number of scientists, and contributions, from the USSR (stilI existing at the time of the meeting) and from East Berlin. The large number of contributions proposed, originally, as oral presentations, could not be fitted in the schedule of the two-day limit which the participants to the previous meetings had recommended. To take account of these contributions, poster sessions were held, combined with extended discussion time. This intensified personal interaction was much appreciated by the participants.

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emMonitoring of Gaseous Pollutants by Tunable Diode Lasers/em is divided into four sections: I -- Atmospheric Trace Gas Detection; II -- Diode Lasers and Their Properties, including Progress in IV-VI Physics and Optoelectronic Devices; III -- Techniques, Systems, Components; IV - Special Applications. br/ Atmospheric trace gas detection was of central interest, and the presentations clearly demonstrate the impressive capabilities of the diode laser technique. Reports on IV-VI mid-infrared diode lasers stress those properties -- radiation noise and emission linewidth -- which are essential for application to ultra-high sensitivity pollution monitoring. Two reports on III-V systems emitting at wavelengths shorter than 3 mum show that the less severe cooling requirements can lead to more compact equipment which can be used to detect pollutants via overtone absorption bands. The presentations on IV-VI physics and devices stress the physical and technological aspects of mid-infrared diode lasers. Laterally structured diode lasers are discussed in detail. There is also extensive material which compares traditional AM and the more recent FM techniques. The reports on special applications point to new directions for research, thus rounding off a complete, expert discussion of a vital research area. br/

Contenu
High Precision Tunable Diode Laser Absorption Sspectroscopy Aapplication for Mmeasuring Llong Llived Aatmospheric Ggases.- Formation and Emission of Atmospheric Greenhouse Gases in the Combustion of Fossil Fuels: Monitoring by Tunable Diode Laser Spectroscopy.- Measurements of H2O2 in the Grand Canyon by Tunable Diode Laser Spectrometry During the Navajo Generating Station Visibility Study.- Measurement of Atmospheric Species by Mid-Infrared and Near-Infrared Tunable Diode Laser Absorption.- Pollution Gas Detection in Free Atmosphere Beyond Atmospheric Windows.- A Portable Bistatic Monitor for Atmospheric Methane Density with up to 240m Optical Path.- Embossed Grating DFB-BH Lead Chalcogenide Diode Lasers.- Epitaxial Growth of Laterally Structured Lead Chalcogenide Lasers.- Semiconductor Lasers and Photodiodes for Gas Analysis in the Spectral Range 1.82.5 ?m.- Linewidth and Noise of Lead Chalcogenide Diode Lasers.- Measurements of IV-VI Diode Laser Near- and Farfield Distributions.- Recent Developments in MBE Grown Pb1-xEUxSeyTe1-y/Pb1-vSn1-vTe diode lasers for high resolution spectroscopy.- Contributions to the Theory of Auger Recombination in Lead Chalcogenides.- Thermodynamics of Quasiternary Systems Containing IV-VI-Semiconductors.- Development of Lead-Chalcogenide Tunable Diode Lasers for 3 to 4 ?m Spectral Region at Lebedev Physical Institute.- Optical Properties of High Energy Gap Lead Salts.- Picosecond Infrared Spectroscopy of Lead Chalcogenide Semiconductors.- Optical Nonlinearities of Free Carriers in PbSe.- Limitations of Compound Segregation in the Vapour Crystal Growth of Solid Solution Crystals.- PbSnMnTe Semimagnetic Semiconductors: Carrier Concentration Controlled Magnetic Properties.- Structural and Electrical Properties of PbSe Grown by theVertical Bridgman Method.- Magnetically Tuned Pb1-xMnxSe and Pb1-x-yMnxSnySe diode lasers.- Se-Diffused PbS1-xSex-Homolasers in the Temperature Range From 5 to 100 K.- Photovoltaic Infrared Sensor Arrays in Monolithic Lead Chalcogenides on Silicon.- Thermal Mismatch Strain Relaxation of Epitaxial IV-VI Layers on Si(111) Substrates at Cryogenic Temperatures.- MBE Growth and Characterization of PbSe Layers on Si(111) Using (Ba, Ca)F2 as Buffer Layers.- RHEED Investigations of PbTe and Pb1-xEuxTe Surfaces During MBE Growth.- Scanning Tunneling Microscopy Analysis of Single Crystal PbSe-Surfaces and Epitaxial Layers on BaF2.- State of the Art of TDLS in the USSR.- Development of a Prototype IR-FM Absorption Spectrometer Design Criteria and System Performance.- A TTFM Spectrometer for Detection of Transient Radical Species: 2 v1 Overtone Absorption Lines of HO2 at 1.5 ?m.- Line Narrowing and Frequency Control of Lead-Salt Diode Lasers by Optical Feedback.- Fiber Optic Accessories for Molecular Spectroscopy and Gas Analysis with Tunable Diode Lasers in the Middle Infrared.- New Developments in Computer-Controlled Diode Laser Spectroscopy.- Measurement of Pressure-Effects with a Stabilized IR-Diode Laser Spectrometer.- Pressure Broadening Parameter of NOx Using TDLAS.- The v3 Band of SO2-Line Parameters for Atmospheric Monitoring.- Pure Absorption Spectroscopy of Molecular Oxygen Using a CW AlGaAs Laser.- Spectroscopic Measurements of the v2+2 v3 Band of CH4 with a 1.3 ?m InGaAsP Diode Laser.- Sensitive Detection of Acetylene Absorption in the Visible Using a Stabilized AlGaAs Diode Laser.- Fast Scanning Laser DOAS, an Ultrasensitive Technique for Monitoring Tropospheric Trace Gases.- Enclosive Flow Cooling: Concept of a New Method for Simplifying Complex MolecularSpectra.- TDLS Analysis of Water Vapour Traces in Semiconductor Process Gas.- Determination of Unburned Fuel in the Wall Boundary Layer of Methane/Air Flames.- Analysis of Trace Components in Automomotive Exhaust Gas.- Application of Diode Laser Spectroscopy on the Measurement of Boundary Layer -Induced Temperature Changes in Shock Tubes.- A TDL- and FT-IR Study of the Reaction NO3+HO2 ? OH+NO2+O2.- Measurements of the 13C/12C Ratio in Methane Using a Tunable Diode Laser Absorption Spectrometer.- Application of Tunable Diode Lasers for Human Expiration Diagnostics.- Author Index.