Novel approaches to THz sources and detectors at room temperature

The development of widely-tunable monochromatic THz sources is described. These sources are based on difference-frequency generation (DFG) in GaSe, ZnGeP₂, and GaP, respectively. Using a GaSe crystal the output wavelength was tuned in the range of from 58.2 mum to 3540 mum (from 172 cm^-1 to 2.82 cm^-1) with the peak power reaching 209 W. On the other hand, based on DFG in a ZnGeP₂ crystal the output wavelength was tuned in the ranges of 83.1-1642 mum and 80.2-1416 mum for two phase-matching configurations, respectively. The output power reached 134 W. Finally, using a GaP crystal the output wavelength was tuned in the range of 71.1-2830 mum whereas the highest peak power was 15.6 W