Line shapes of near-infrared DFB and VCSEL diode lasers under the influence of system back reflections

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Details zur Publikation

Autor(en): Engelbrecht R, Lins B, Zinn P, Buchtal R, Schmauß B
Zeitschrift: Applied Physics B-Lasers and Optics
Verlag: Springer Verlag (Germany)
Jahr der Veröffentlichung: 2012
ISSN: 0946-2171
Sprache: Englisch


Laser diode line widths and line shapes are experimentally investigated in dependence on the diode current and on back reflections from an optical system. Four distributed-feedback (DFB)-type diode lasers and two vertical-cavity surface-emitting lasers (VCSELs) have been tested within the same optical setup and using the same fitting methods. System back reflection ratios of light reflected back to the laser have been varied between -1 dB and -45 dB and were below -60 dB when all reflections were blocked. The background of this investigation is the evaluation of different laser types with respect to their suitability for sensor applications in which optical back reflections may occur, for example tunable diode-laser spectroscopy (TDLS). While DFB-type lasers showed almost pure Lorentzian line shapes and line widths of a few MHz, the tested VCSELs had a strong Gaussian contribution to the line shape, indicating stronger 1/f noise, which was also observed in the relative intensity noise of these particular lasers. System reflection ratios above -25 dB had strong effects on the line width in both DFB diode lasers and VCSELs, while some influences have been observed at even lower reflection ratios for DFB diode lasers. As much smaller reflection ratios are typically required in TDLS systems to avoid etalon-like fringes and self-mixing interference effects, we conclude that the influence on the line width is not the most important reason to minimize back reflections in practical TDLS systems or to choose one type of diode laser over the other. © 2012 Springer-Verlag.

FAU-Autoren / FAU-Herausgeber

Engelbrecht, Rainer PD Dr.
Lehrstuhl für Hochfrequenztechnik
Lins, Bastian
Lehrstuhl für Technische Thermodynamik
Schmauß, Bernhard Prof. Dr.-Ing.
Professur für Hochfrequenztechnik mit dem Schwerpunkt Optische Hochfrequenztechnik und Photonik

Autor(en) der externen Einrichtung(en)
Drägerwerk AG & Co. KGaA


Engelbrecht, R., Lins, B., Zinn, P., Buchtal, R., & Schmauß, B. (2012). Line shapes of near-infrared DFB and VCSEL diode lasers under the influence of system back reflections. Applied Physics B-Lasers and Optics.

Engelbrecht, Rainer, et al. "Line shapes of near-infrared DFB and VCSEL diode lasers under the influence of system back reflections." Applied Physics B-Lasers and Optics (2012).


Zuletzt aktualisiert 2018-07-08 um 04:39