Terahertz technologies

Terahertz spectroscopy using quantum-cascade lasers

¹ German Aerospace Center (DLR), Institute of Optical Sensor Systems, Rutherfordstraße 2, 12489 Berlin, Germany
² Humboldt-Universität zu Berlin, Department of Physics, Newtonstr. 15, 12489 Berlin, Germany
³ Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V., Hausvogteiplatz 5−7, 10117 Berlin, Germany

^* e-mail: Heinz-Wilhelm.Huebers@dlr.de

Abstract

Terahertz (THz) quantum-cascade lasers (QCLs) provide powerful, narrow-band, and frequencytunable radiation, which makes them ideal sources for high-resolution molecular spectroscopy. A first application of a THz QCL has been as local oscillator in a heterodyne spectrometer for astronomy on board a Boeing 747. For laboratory spectroscopy, QCLs close the so-called THz gap and enable new research topics.