The research objective of this proposal is the investigation and development of widely and continuously tunable terahertz quantum-cascade lasers and other active devices based upon monolithic and voltage tunable metamaterial waveguides. These waveguides are based on the transmission-line metamaterial concept in which the dispersion relation is tuned by electrical control of integrated capacitive elements. Goals include demonstration of widely tunable terahertz laser sources in various configurations, including tunable distributed feedback lasers, tunable master-oscillator power-amplifiers, and beam-steerable phased-array THz laser emitters.
Intellectual Merit The intellectual merit is the integration of tunable metamaterial concepts with laser waveguides, in which propagation is sensitively dependent on values of embedded circuit elements. This approach can achieve a much wider range of tunability than can be achieved using temperature or other electrical techniques, with a high degree of monolithic integration. The demonstration of amplifier and distributed feedback configurations will allow the output power to be scaled to several milliwatts or greater with a directive beam pattern.
Broader Impacts The broader impacts lie in the development of a new approach for achieving tunable semiconductor lasers. Additionally, terahertz technology requires improved sources and detectors for sensing, imaging, and spectroscopy. The core of the educational plan is to enhance undergraduate research within the Electrical Engineering department through the development of a coordinated publicity, outreach, and training program, as well as directly employing undergraduates in this research. Multiple campus resources will be leveraged to attract and fund underrepresented minority students to this research and engineering in general.
