Continuous wave intracavity terahertz source

In this paper, the authors present a room temperature operating, compact and tunable CW THz source. With this device a generation of milliwatt power levels is feasible. The system is based on intracavity difference frequency generation (DFG) within a dual colour vertical external cavity surface emitting laser (VECSEL). A high conversion efficiency is achieved by using the extremely high circulating intracavity fields to mix the two laser modes within a nonlinear crystal. This generation scheme does not only provide access to the high intracavity infrared intensities but also allows for a compact and robust setup.