The objective of this research is to explore the realization and study the performance of a multiband imaging receiver system that potentially provides the highest available heterodyne detection sensitivity in the frequency range of 1-3 THz. The approach is to integrate a pair of identical superconducting hot-electron bolometers (HEBs) into a dual-polarization sinuous antenna to form a quasi-optical balanced mixer configuration. To further reduce the system noise, a superconducting microwave hybrid will be integrated for IF output. THz multi-band/reconfigurable frequency selective surfaces (FSSs) will also be explored to be employed in the receiver system. The research program consists of detailed design, simulation, development, and experimental demonstration of prototype receivers operating in the sub-millimeterwave through THz regimes.
The program's intellectual merit centers on the challenges and opportunities offered by integrating two HEBs into a sinuous antenna to realize a high performance receiver system suitable for multiband THz detection and imaging applications. The ultra-low system noise and multi-frequency operation are achieved by novel approaches of quasi-optical balanced mixer configuration, the integration of superconducting IF hybrids and the utilization of multiband/tunable THz FSSs. Advances in THz devices, circuits design and integration technology are expected. Insights gained may be transferrable to other THz detection and imaging technologies.
The broader impacts include both the creation of new scientific/engineering knowledge, as well as contributions to university education. In addition to the THz community, this work will benefit a wide range of science disciplines such as astronomy, atmospheric physics, chemical/biological sensing, and medical diagnostics. The graduate students in this program will be exposed to the full scope of the system design process, from devices to the system level. Undergraduates will be involved through summer and honors thesis research.
