Interaction of Semiconductor Laser Dynamics with THz Radiation

Abstract

We discuss the generation and detection of THz radiation with semiconductor diode lasers. First, we analyze the generation of THz radiation by investigating a semiconductor laser in an external cavity arrangement that supports two color operation with tunable difference frequency. Second, the opposite process, i.e., THz detection with diode lasers is investigated. For that purpose, we inject THz radiation into the active region of a diode laser and analyze its dynamics under this injection. We observe a voltage variation over the p-n-junction depending on the injected THz power and compare the measured signal to the response of a standard Golay cell. Finally, we review our results with particular emphasis on completely diode-laser based THz imaging or spectroscopy systems.