Title: Electromagnetic Lego
Date: January 20, 2022
Time: 3:00pm
Abstract:
When Smith, Pendry and others started tinkering with split-ring resonators (SRR) for realizing double negative media, little did we know then these earlier ground breaking works ushered the beginning of a completely different perspective on designing of all types of electromagnetics-based systems. The SRR, or any other resonator that has dimensions much smaller than the wavelength were used as the building blocks for single and double negative media and even near-zero media. While these exotic media enabled cloaking and design of dispersion-controlled media, the applications were largely limited. The concept of a building block, however, might hold the key to a much larger class of designs and applications. Back in the seventeenth century, Huygens conceived the idea of elementary sources as forming the radiated or scattered field. His extraordinary perception of the mechanism of the wave phenomenon preceded the full-fledged development of Maxwell equations by more than 150 years. While Huygens work was an attempt to understand the wave phenomenon through analysis, we pose the question of whether we can extend the concept of building blocks or elementary sources to synthesize electromagnetics based radiating systems. If all things in nature are composed of identical building blocks, can we conceive of a similar construction of electromagnetics systems in general?
In this talk, I will focus on the importance of understanding what is meant by metamaterial, metasurface particles or electrically-small resonators in general. Unlike building blocks used for other physical systems that are not founded on the action-at-a-distance phenomena, the electrically-small resonators, or electromagnetic Legos are more intriguing as their strong coupling needs to be tailored to ensure their desired operation. Several new designs of electromagnetics systems from lenses, to sensors and antennas will be discussed in details covering a broad range of activities conducted in my research group at Waterloo. Focusing on the concept of a building block will naturally reignite strong interest in understanding the fundamental physical phenomenon of radiation and hopefully would lead to asking important questions that were considered of secondary importance in earlier times.
Biography:
Omar M. Ramahi is a professor in the Department of Electrical and Computer Engineering at the University of Waterloo. He received BS degrees in mathematics and electrical and computer engineering from Oregon State University, Corvallis, OR. He received his MS and PhD degrees in electrical and computer engineering from the University of Illinois at Urbana-Champaign. From 1993 to 2000, he worked at Digital Equipment Corporation (presently, HP) where he was a member of the Alpha Server Product Development Group. In 2000, he joined the James Clark School of Engineering at the University of Maryland at College Park as an assistant professor and later as a tenured associate professor. At Maryland he was also a faculty member of the Center for Advanced Life Cycle Engineering (CALCE) Electronic Products and Systems Center.
Professor Ramahi’s research interests include radiating systems, renewable energy technology, biomedical applications of electromagnetic waves and fields, electromagnetic compatibility and interference, metamaterials and its engineering applications, and material measurements.
Professor Ramahi is a co-author of the book EMI/EMC Computational Modeling Handbook, 2nd Ed. He has authored more than 450 journal and conference papers. He served as a consultant to several companies and co-founded Applied Electromagnetic Technology and Wave Intelligence Inc. He won the Excellent Paper Award in the 2004 International Symposium on Electromagnetic Compatibility, Sendai, Japan, and the 2010 University of Waterloo Award for Excellence in Graduate Supervision. In 2009, he was elected IEEE Fellow, and in 2012, he was awarded the IEEE Electromagnetic Compatibility Society Technical Achievement Award. From 2007-2015, he served as an Associate Editor for the IEEE Transactions on Advanced Packaging. From 2010-2012, he served as an IEEE EMC Society Distinguished Lecturer.