SBIR Phase I: A Portable High-Power Tunable Terahertz Source using a Two-Color VECSEL

This Small Business Innovation Research (SBIR) Phase I project will develop a novel room temperature, narrow-line, high power vertical external-cavity semiconductor laser (VECSEL) THz source based on difference-frequency-mixing of high-power circulating dual wavelength fields in a high-finesse cavity. Semiconductor quantum-well gain media have the unique property that multiple wavelengths can be simultaneously generated within single laser cavity through a physical process known as spectral hole-burning. A preliminary experiment has demonstrated 3mW of THz power, far exceeding (by six orders of magnitude) the existing record for CW THz sources using optical generation schemes. The project goal is to develop an integrated source/detection solution for detection of and countermeasures to improvised explosive devices. The broader impacts/commercial potential of this project will be a price competitive and comprehensive solution that would impact a broad range of defense and commercial applications. Potential THz applications range from the standoff detection of explosives and chemical and biological agents, to the measurement of in vivo tissue water content, fat content, blood glucose and cholesterol contents and the diagnosis of cancer. In dentistry THz may provide a powerful alternative to X-ray images. In the food processing industry THz waves will help detect E-coli and other poisonous bacteria as well as small imperfections in packaging. THz spectroscopic imaging can help Law-enforcement with the detection of prohibited substances and counterfeit bank notes. This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).