Properties of quantum cascade lasers and their use in spectroscopy

Quantum cascade lasers (QCLs) become a very interesting new light source for application in process monitoring and environmental analysis. Latest results show their large potential for MIR-spectroscopy. However, their properties are not completely understood. In particular, the behaviour within the short pulses is of major interest. We present data about heating and cooling of the active zone of the laser, wavelength tuning and gas measurements performed with a measurement system using a QCL and a fast peltier cooled detector. The wide tuning range of these lasers during a singel pulse provides the possibility to completely tune over isolated absorptions lines and perform direct transmission spectroscopy on even a set of absorption lines.