Measurements of the alpha factor of a distributed-feedback quantum cascade laser by an optical feedback self-mixing technique

Jens von Staden; Tobias Gensty; Wolfgang Elsässer; Guido Giuliani; Christian Mann

doi:10.1364/ol.31.002574

Measurements of the alpha factor of a distributed-feedback quantum cascade laser by an optical feedback self-mixing technique

Opt Lett. 2006 Sep 1;31(17):2574-6. doi: 10.1364/ol.31.002574.

Authors

Jens von Staden¹, Tobias Gensty, Wolfgang Elsässer, Guido Giuliani, Christian Mann

Affiliation

¹ Institute of Applied Phsyics, Darmstadt Univeristy of Technology, Schlossgartenstrasse 7, Darmstadt, Germany. jens.von.staden@physik.tu-darmstadt.de

PMID: 16902623
DOI: 10.1364/ol.31.002574

Abstract

We demonstrate measurements of the alpha factor of a distributed-feedback quantum cascade laser (QCL) by using a newly modified self-mixing interferometric technique exploring the laser itself as the detector. We find a strong dependence of the alpha factor on the injection current, ranging from -0.44 at 120 mA to 2.29 at 180 mA, which can be attributed to the inherent physics of QCLs.