Reliable operation of 785 nm DFB diode lasers for rapid Raman spectroscopy

M. Maiwald, G. Erbert, A. Klehr, B. Sumpf, H. Wenzel
Ferdinand-Braun-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin, Germany

T. Laurent, J. Wiedmann
eagleyard Photonics GmbH, Rudower Chaussee 29, D-12489 Berlin, Germany

H.-D. Kronfeldt, H. Schmidt
Technische Universität Berlin, Institut für Optik und Atomare Physik, Hardenbergstrasse 36, D-10623 Berlin, Germany

Published in:
Proc. of SPIE Vol. 6456, 64560W, (2007).
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Abstract:
Experimental results on RW and BA DFB lasers emitting at 785 nm suitable for Raman spectroscopy are presented. Optical spectra of the RW DFB laser reveal single mode operation with a side-mode suppression ratio of more than 45 dB at optical output powers up to 163 mW. A reliable operation of more than 8800 h of these devices is demonstrated. Within a spectral width of 0.6 nm, more than 99.9% of 1.1 W optical power of the BA DFB laser emitting at 785 nm are included. Raman measurements with RW and BA DFB lasers as excitation light sources and polystyrene as a test sample are presented. At an output power of 1.1 W of the BA device the integration time for the Raman measurement could be reduced to 50 ms.

Keywords:
Semiconductor lasers, distributed-feedback lasers, ridge-waveguide lasers, broad-area lasers, high-power lasers, Raman spectroscopy

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