1. Ferdinand-Braun-Institut
  2. Forschung
  3. Publikationen
  4. Application of 940 nm high-pow ...

Publikationen

Konferenzbeiträge - bei Terminen
Eine Reihe von Hochformatbroschüren ist aufrecht angeordnet. Die Cover zeigen Titel und Informationen zu verschiedenen Themen.

Dissertationen
Collage aus mehreren Patentschriften aus verschiedenen Ländern, darunter Deutschland, die USA und Japan. Es werden Informationen wie Aktenzeichen, Anmeldedaten und Patentnummern präsentiert.

Patente

Application of 940 nm high-power DFB lasers for line-broadening measurements at normal pressure using a robust and compact setup

B. Sumpf, A. Klehr, G. Erbert, G. Tränkle

Published in:

Appl. Phys. B, vol. 106, no. 2, pp. 357-364 (2012).

Abstract:

High-power distributed-feedback (DFB) lasers for the wavelength range near 940 nm (i.e. about 10,600 cm-1) were used for line-broadening measurements of individual rotational-vibrational absorption lines of water vapour at atmospheric pressure using a minimalist set-up. The laser has a maximum output power larger than 500 mW. Over the whole power range from threshold to maximum power, it operates in single mode operation with a tuning range of 4.7 nm, i.e. 50 cm-1, at 20°C. With an emission line-width ≤2 MHz (0.66×10-4 cm-1), the device is well suited for high-resolution spectroscopy.
Instead using a sophisticated optical set-up with a multi-reflection cell to obtain the necessary path length for measuring rather weak absorption lines, in this work a 4" integrating sphere was used as a multi-reflection cell providing an effective absorption length of 6.7 m. The laser was placed without any optical elements in front of the entrance hole.
The power-current-characteristics, the spectral features of the diode laser, and examples for the spectral tuning will be given. In the spectral range from 10,584.3 cm-1 to 10,670.2 cm-1, line broadening coefficients in the range 0.059 cm-1/atm ≤ γH2O-air ≤ 0.112 cm-1/atm were measured for 18 H2O absorption lines from the 2ν1+ν3-band and 7 H2O lines from the 3ν1-band. The good agreement of the measured air-broadening coefficients with data from the literature for absorption lines with a J"≤4 and Ka"≤3 proves the applicability of this low-cost set-up. Some deviations between the literature and this work were observed for lines from the 2ν1+ν3-band with larger J">4 and Ka"=3.

Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Straße 4, D-12489 Berlin, Germany

© Springer-Verlag 2012. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the Springer-Verlag.

Full version in pdf-format.