Spatially resolved thermoreflectance study of facet temperature in quantum cascade lasers

Abstract

Abstract In the present work, we use spatially resolved thermoreflectance (SR TR) to measure temperature distribution over the facet of pulsed operated quantum cascade lasers. The laser beam probes the change in the refractive index caused by current‐induced heating of working device. The technique has a spatial resolution of about ∼1 μm and temperature resolution better than 1 K. It gives an insight into distribution and relative importance of heat sources within the laser. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)