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Diode laser spectroscopy in extended wavelength ranges

Gustafsson, Ulf LU (2000) In Lund reports on atomic physics LRAP 253.
Abstract
Diode laser spectroscopy performed in the ultraviolet, visible and infrared spectral regions is presented.



The accessible wavelength range for visible and near-infrared diode lasers is extended by the use of sum- and difference-frequency generation. Sum-frequency generation to the ultraviolet spectral region was employed using a blue and a red diode laser. Mercury spectroscopy was demonstrated with the generated ultraviolet beam. Difference-frequency generation with two near-infrared diode lasers has been utilised to extend the wavelength range to the mid-infrared spectral region. With each of the three wavelengths resonant with a molecular species, detection of molecular oxygen, water vapour, and methane was achieved... (More)
Diode laser spectroscopy performed in the ultraviolet, visible and infrared spectral regions is presented.



The accessible wavelength range for visible and near-infrared diode lasers is extended by the use of sum- and difference-frequency generation. Sum-frequency generation to the ultraviolet spectral region was employed using a blue and a red diode laser. Mercury spectroscopy was demonstrated with the generated ultraviolet beam. Difference-frequency generation with two near-infrared diode lasers has been utilised to extend the wavelength range to the mid-infrared spectral region. With each of the three wavelengths resonant with a molecular species, detection of molecular oxygen, water vapour, and methane was achieved simultaneously.



By employing frequency modulation techniques, detection limits are improved by orders of magnitude compared to direct absorption measurements. Frequency modulated absorption spectroscopy in the red spectral region was performed for sensitive long-path absorption monitoring of nitrogen dioxide. The possibility of employing frequency modulation techniques for sensitive absorption measurements in the blue and ultraviolet spectral region has also been investigated. Atomic spectroscopy in the blue and red spectral region has been demonstrated, providing a pedagogical demonstration of the theory for Doppler broadening.



A new instrument, using a coupled cavity diode laser, has been constructed and employed for aerosol particle sizing and identification. The size of a single aerosol particle is determined by an extinction loss signal and identification is performed using a diffraction image.



A compact fluorosensor utilising a violet diode laser as an excitation source combined with an integrated spectrometer and fibre-optic sampling for the monitoring of fluorescence signatures was developed. The potential of this new instrument was demonstrated in measurements on vegetation and human malignant skin lesions. (Less)
Please use this url to cite or link to this publication:
author
opponent
  • Professor Sigrist, Markus W.
organization
publishing date
type
Thesis
publication status
published
subject
keywords
diode-laser spectroscopy, frequency-modulation spectroscopy, frequency conversion, fluorescence spectroscopy, scattering, diffraction, Fysicumarkivet A:2000:Gustafsson, Atomic and molecular physics, Atom- och molekylärfysik, absorption spectroscopy
in
Lund reports on atomic physics
volume
LRAP 253
pages
176 pages
publisher
Department of Physics, Lund University
defense location
Physics Department, Lecture Hall B
defense date
2000-04-28 10:15
external identifiers
  • Other:ISRN: LUTFD2/(TFAF-1042)/1-80(2000)
ISBN
91-7874-047-9
language
English
LU publication?
yes
id
6062b3b8-a76d-47a6-a328-8519bf97a45e (old id 40511)
date added to LUP
2007-06-21 10:53:27
date last changed
2016-09-19 08:45:08
@phdthesis{6062b3b8-a76d-47a6-a328-8519bf97a45e,
  abstract     = {Diode laser spectroscopy performed in the ultraviolet, visible and infrared spectral regions is presented.<br/><br>
<br/><br>
The accessible wavelength range for visible and near-infrared diode lasers is extended by the use of sum- and difference-frequency generation. Sum-frequency generation to the ultraviolet spectral region was employed using a blue and a red diode laser. Mercury spectroscopy was demonstrated with the generated ultraviolet beam. Difference-frequency generation with two near-infrared diode lasers has been utilised to extend the wavelength range to the mid-infrared spectral region. With each of the three wavelengths resonant with a molecular species, detection of molecular oxygen, water vapour, and methane was achieved simultaneously.<br/><br>
<br/><br>
By employing frequency modulation techniques, detection limits are improved by orders of magnitude compared to direct absorption measurements. Frequency modulated absorption spectroscopy in the red spectral region was performed for sensitive long-path absorption monitoring of nitrogen dioxide. The possibility of employing frequency modulation techniques for sensitive absorption measurements in the blue and ultraviolet spectral region has also been investigated. Atomic spectroscopy in the blue and red spectral region has been demonstrated, providing a pedagogical demonstration of the theory for Doppler broadening.<br/><br>
<br/><br>
A new instrument, using a coupled cavity diode laser, has been constructed and employed for aerosol particle sizing and identification. The size of a single aerosol particle is determined by an extinction loss signal and identification is performed using a diffraction image.<br/><br>
<br/><br>
A compact fluorosensor utilising a violet diode laser as an excitation source combined with an integrated spectrometer and fibre-optic sampling for the monitoring of fluorescence signatures was developed. The potential of this new instrument was demonstrated in measurements on vegetation and human malignant skin lesions.},
  author       = {Gustafsson, Ulf},
  isbn         = {91-7874-047-9},
  keyword      = {diode-laser spectroscopy,frequency-modulation spectroscopy,frequency conversion,fluorescence spectroscopy,scattering,diffraction,Fysicumarkivet A:2000:Gustafsson,Atomic and molecular physics,Atom- och molekylärfysik,absorption spectroscopy},
  language     = {eng},
  pages        = {176},
  publisher    = {Department of Physics, Lund University},
  school       = {Lund University},
  series       = {Lund reports on atomic physics},
  title        = {Diode laser spectroscopy in extended wavelength ranges},
  volume       = {LRAP 253},
  year         = {2000},
}