In this STTR program we will first develop a high power, very narrow linewidth (CW), tunable, compact, room temperature terahertz (THz) spectroscopic system and then use this to begin development of experimentally obtained THz spectra. The THz source is based on our previous simulation and initial experimental demonstration of a novel nested waveguide structure using difference frequency generation which has achieved a power- normalized conversion efficiency of 1.3 x 10-7 W-1, about 23X larger than the best previously reported results and with a spectral linewidth ~ 1-2 MHz. In this work we expect to achieve a power- normalized conversion efficiency of at least 7 x 10-6 W-1, and an absolute output power approaching 1mW. The high conversion efficiency and output power results from the structure of the nested waveguide, which permits independent optimization of the optical pump and THz waveguides.
Keywords: Thz, Spectroscopy, Thz Source, Far-Infrared Source, Chemical Fingerprinting
