The objective of the research is to design and develop a suite of electronic devices operating at terahertz frequencies. The approach is based on the active control of metamaterial structures using plasma wave resonant behavior of the gated two-dimensional electron gas in the channel of GaAs HEMT devices.
Intellectual Merit: The research is focused on the creation of unique metamaterial/pHEMT hybrid devices to fill the "terahertz gap," where very few components exist today. The fundamental approach uniquely combines the emerging field of electromagnetic metamaterials with novel plasma wave electronic transport phenomena in transistors. The plasma wave behavior in sub-micron transistors offers the unique possibility to detect and modulate terahertz frequency signals. Modulator and demodulator device architectures will be developed to facilitate wireless communications in the terahertz regime with targeted data rates exceeding hundreds of gigabits per second.
Broader Impacts: The research will help catalyze development in diverse areas such as high data rate wireless communications, terahertz spectroscopy for cancer detection and tools for homeland security. The project will establish research and teaching laboratories at Boston College and Tufts University in the area of metamaterials and terahertz electronics. The project will support diversity and outreach activities through research programs for undergraduates and summer programs for students from under-represented groups, The researchers also plan to offer lectures at local high schools primarily in minority-dominated neighborhoods, and participate actively in K-12 student-teacher mentorship programs established at Tufts University and Boston College.
The main objective of the proposed research was to make progress in the next generation of devices for terahertz frequencies, a band of frequencies which has tremendous potential in sensing, security and communications, but developments have been slow to come because of lack of sources, detectors, modulators etc . This project took this challenge to implement a new suite of terahertz devices, specifically modulators and detectors based on the active control of metamaterial structures implemented in GaAs pHEMT processes. The research plan to meet these goals was based on four stages of development, consisting of: (i) Device modeling and design, (ii) Fabrication, (iii) Device characterization, and (iv) Performance analysis. Intellectual Merit: We were succesful in implementing modulators using pHEMT process that operated at terahertz frequencies. This has the potential to push the boundaries for wireless communication at greater speeds. We also implemented a new class of focal plan array imagers using metamaterials as detectors. This has the potential to make imagers for sensing and homeland security. We also showed how one can harvest RF power using metamaterial resonator which has potential in powering of medical implants and biomedical devices. Broader Impact: The project trained 3 different graduate students who have now become experts in the field and plan to pursue a research and development career. Several undergraduate students were involved in the research who have also pubished themselves and made a positive impact in the field. Finally several research papers have been published that highlight the outcomes of this research. The research also had a diverse pool with women and members from under-represnted groups actively involved in the project.
