Efficient high power tunable THz source based on all fiber-based pulsed fiber lasers at 1.55 micron

We propose to develop a fiber-based, high power, narrow linewidth, and tunable THz source by leveraging our proprietary fiber laser at ~ 1.55 micron and patented THz techniques. This proposed high power fiber-based THz source will be generated by using a ZnGeP2 crystal based on difference-frequency generation (DFG) pumped by high power pulsed fiber lasers in MOPA, which will reach a high power of 10-100 mW, a widely tuning range of 0.2-6 THz, and a narrow linewidth of <500 MHz. This proposal will use an external power cavity to enhance the conversion efficiency of parametric THz generation. This efficient pump recycling has the possibility to enhance the efficiency close the Manley-Rowe limit. BENEFIT: Currently, the THz spectral region has been underutilized because of the inadequacy of THz sources. The proposed THz source is expected to break this limit, which has the advantages of compact, high power, high spectral resolution, extremely wide tunability, and room temperature operation. So this proposed THz source will have large potential market in THz applications, such as real-time imaging, non-destructive evaluation, stand-off sensing and chemical detection and analysis. The proposed THz source can be used by military agencies for communications on the battlefield or in space, trace detection of hazardous materials and explosives in filed due to the fast response, room-temperature operation, low noise, and high spectral resolution, used in atmospheric environment sensing, airport and subway for screening hazardous materials and explosives from a wide-spectrum of the population, and used in research and development of biological materials, pharmaceuticals and other chemicals because THz spectrum can reveal the unique structure features of the molecules.