CAREER: Novel Microplasmas for Highly Compact and Versatile RF Electronics

University Of Toledo, Toledo OH

Investigators

Abstract

Due to the increasingly congested and contested spectrum, reconfigurable RF electronics have become a subject of extensive research. Semiconductor devices, microelectromechanical systems (MEMS), liquid crystals, and ferromagnetic materials have conventionally served as tools for RF tuning. However, these technologies are constrained by limited tuning ranges and low power handling capabilities. To overcome these limitations, cold plasma presents a promising solution. Manipulating internal parameters, such as electron density, gas type, and pressure, offers extensive tunability over plasma electromagnetic properties. Cold plasmas have already provided significant advantages across various societally relevant applications, such as plasma medicine, food preservation, water treatment, plasma fertilizer, electric propulsion systems, sterilization, and semiconductor fabrication. This research explores fundamental physics and demonstrates techniques for establishing stable microplasmas with exceptional electromagnetic properties for versatile RF electronics. To realize this vision, (1) theoretical and modeling frameworks for high-frequency microplasmas will be developed, (2) a closed-loop microplasma monitoring and control system will be investigated, and (3) stable microplasmas with unprecedented electromagnetic features will be realized. Undergraduate and graduate students will be involved, a unique educational plasma lab will be established, and a circuit-based electromagnetic-plasma simulator will be developed. In addition, various synergistic outreach activities will be conducted, including Toledo Excel summer camps for underrepresented students. By combining innovative research, educational initiatives, and outreach efforts, this endeavor aspires to advance the landscape of reconfigurable RF electronics, paving the way for emerging multi-objective and multi-frequency systems. Plasmas represent rapidly reconfigurable media that can be controlled on nanosecond timescales. The interaction between microplasmas and electromagnetic waves introduces a new field of significant applications that can be categorized as "Gaseous Microelectronics." This study aims to push the boundaries of plasma science by exploring widely tunable microplasmas capable of unconventional interactions with electromagnetic waves. This exceptional behavior will be achieved through fundamental understanding and precise control of microplasma kinetics. While some efforts have been made in plasma-based RF electronics, this research field has not yet been comprehensively explored, specifically for microplasmas with extreme electromagnetic features—a knowledge gap this project aims to address. To pursue this overarching objective, a novel closed-loop control system, including innovative diagnostic techniques, will be developed to accurately manipulate microplasmas. With all theoretical, numerical, and experimental investigations involved, the goal is to realize (i) high-Q microplasma varactors with extraordinary tunability, (ii) natural epsilon-near-zero (ENZ) microplasmas, and (iii) low-loss negative index materials (NIMs). Rapidly and widely tunable, low-loss, and high-power materials for high-frequency tuning do not currently exist, but this research can change this paradigm. By leveraging these unique materials, more efficient utilization of the electromagnetic spectrum can be achieved, effectively meeting the escalating demand for wireless services. In addition, these features will benefit emerging sensing, biomedical, and space applications, addressing critical needs in these domains and fostering technological innovations. 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.