This Small Business Innovation Research Phase I project addresses development of a terahertz imaging focal plane array. The detectors are thin cantilevered strips whose physical properties change with temperature. The research objectives include modeling and design of the cantilevers, assessment of optical vs. electronic irradiance readout, means for maximizing irradiance absorption, and techniques for image array readout. These objectives will be pursued within the framework of Phase II production of functioning arrays. From earlier work in the thermal infrared, the detector array is projected to be very sensitive compared to existing bolometers, with a response time permitting high frame rates, high pixel count, and development of imaging arrays of high resolution (pixel count).
BROADER IMPACT Terahertz radiation imaging offers many of the benefits of X-rays, without ionizing radiation. THz imaging spectroscopy offers a new and very powerful tool for selectively imaging and identifying complex chemical species. Availability of a producible and cost-effective THz-imaging focal plane array with high pixel count, high sensitivity and high frame rate will enable production of new classes of systems for security (imaging through clothing and packaging materials, metal detection), identification and recognition (using subcutaneous blood vessel patterns), taggants (with THz-based coding buried in plastic cards or chips), diagnostic medicine (non-invasive exploration of subcutaneous tissue, interior thermal mapping), and rapid identification and characterization of organic and pharmaceutical materials.