CAREER: Harnessing Ferri- and Antiferro-Magnetism for Reconfigurable Wireless Transcievers

Cornell University, Ithaca NY

Investigators

Abstract

For 5G and 6G next-generation wireless systems accessible to more simultaneous users and sufficiently versatile for worldwide communications, transceivers need to be able to handle more communication bands and tune between them. Full integration of reconfigurable transceiver front ends requires both tunable electric and tunable magnetic components. To date, only integrated electric (i.e., capacitive) components are tunable. This research aims to fill the critical gap in wireless capabilities by creating tunable microwave and millimeter-wave magnetic (i.e., inductive) components. These components will take the form of tunable microwave inductors and tunable resonant waveguides using monolithically integrated magnetoelectric thin films. The uniquely designed magnetoelectric thin films will provide direct in situ and simultaneous control over the permeability and permittivity at much higher frequencies than previously achievable in order to efficiently tune the resonance frequency of wireless communication systems. By integrating these components with transceiver front-ends, this project will demonstrate their impact in enabling adaptive microwave and mm-wave wireless systems for providing widespread 5G and 6G wireless technology. Such reconfigurable transceivers have the potential to increase the capabilities of future sensing, medical, and agricultural systems and broaden access to quality education, thereby improving the standard of living worldwide. The education component focuses on three specific initiatives for increasing URM interest, enrollment, and retention in engineering. Expanding the existing teaching and mentorship efforts through an annual Ph.D. skills seminar course for first year URM doctoral students, creating new hands-on sensors design course for undergraduates, and developing a community-engaged course to cultivate the students for device engineering to increase enrollment. Outreach activity include engineering education initiatives in juvenile detention centers for juvenile justice teachers that has been previously established and will be extended through RET program. This project will build on the PI’s experience in developing tunable gigahertz-range inductors and magneto-electric resonators to develop corresponding capabilities in the microwave and mm-wave regime. Research objectives include design of high-Q magnetic inductors and transmission lines using ferromagnetic CoFeB, ferrimagnetic Gd–Co alloys, a synthetic antiferromagnet made of CoFeB/Ru/CoFeB, and exchange-coupled ferromagnetic Fe65Co35-core/antiferromagnetic-shell nanoparticle composites. These devices will be tested for permeability, self-resonance frequency, and loss tangent to evaluate the best one for microwave and mm-wave device performance. Higher material bandwidth (up to 30 GHz) but lower permeability (below 20) is expected by moving from ferromagnetic to ferrimagnetic/antiferromagnetic thin-films and composites. Subsequently, the highest-efficiency, microwave and mm-wave magnetic inductors and transmission lines will be fully-integrated with transceiver front-ends to evaluate the performance of the complete system. In addition, adaptive transceiver capabilities will be developed by combining the selected magnetic material with piezoelectric AlN to create integrated tunable magnetoelectric devices and will subsequently be incorporated into an integrated transceiver for evaluation of device and system performance by determining the figures of merit required to enable adaptive 5G and 6G wireless technologies. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.