Title: Can perfectly electric conducting obstacles modify the permeability of metamaterial? An investigation using Lorentz, Floquet and full wave models.

Presenter: Dr. Arun K. Bhattacharyya, Principal Scientist/Engineer at Lockheed Martin Space, USA.

Date:  12th October 2023.

Time: 11:00 AM IST.

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Mode: Offline

Venue: NKN Room, E&ECE Department, IIT Kharagpur.

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Abstract of the Talk: An array of perfectly electric conducting (PEC) obstacles in a host dielectric medium modifies the constitutive parameters of the composite medium or metamaterial. Typically, for such a composite medium, the effective (homogenized) parameters are estimated using the Lorentz model. The Lorentz model indicates that inclusion of PEC obstacles in a host medium introduces both electric and magnetic polarizabilities that modify the permittivity and permeability tensors of the composite medium. On the other hand, the Floquet eigenmode analysis shows that the PEC obstacles, while modifying the permittivity tensor, have no effect on the permeability tensor. Hence, as a corollary,  the Floquet model leads us to conclude that a negative permeability metamaterial using PEC obstacles is not possible to obtain.  Interestingly, numerical results obtained from full wave analyses of metamaterial-slabs support the Floquet model. We will present the Lorentz and Floquet models and examine the source of inaccuracy in the Lorentz model. We will discuss the characteristic features of metamaterials made with non-resonant and resonant types of obstacles. Numerical results obtained from four independent models will be compared and discussed. In light of Maxwell’s equations, we will scrutinize the rationality of the claims of “negative-refraction” metamaterials.

Biography of Speaker:  Arun K. Bhattacharyya (Fellow, IEEE) received the B.Eng. degree in electronics and telecommunication engineering from the Bengal Engineering College, University of Calcutta, Kolkata, India, in 1980, and the M.Tech. and Ph.D. degrees from Indian Institute of Technology Kharagpur, Kharagpur, India, in 1982 and 1985, respectively.,From November 1985 to April 1987, he was with the Electrical Engineering Department, University of Manitoba, Winnipeg, MB, Canada, as a Postdoctoral Fellow. From May 1987 to October 1987, he worked for Til-Tek Ltd., Kemptville, ON, Canada, as a Senior Antenna Engineer. In October 1987, he joined the Electrical Engineering Department, University of Saskatchewan, Saskatoon, SK, Canada, as an Assistant Professor and was then promoted to Associate Professor, in 1990. In July 1991, he joined Boeing Satellite Systems (formerly Hughes Space and Communications), Los Angeles, CA, USA, as a Senior Staff Engineer, and then promoted to Scientist and Senior Scientist, in 1994 and 1998, respectively. He became a Technical Fellow of Boeing in 2002. In September 2003, he joined Northrop Grumman Space Technology Group as a Staff Scientist and then became a Distinguished Engineer and an Engineering Fellow. He joined the RF Center of Excellence Group, Lockheed Martin Space Systems, Littleton, CO, USA, in 2014. In 2019, he was a Visiting Professor at Seoul National University, Seoul, South Korea, on leave from Lockheed Martin. He is the author of the book titled Electromagnetic Fields in Multilayered Structures—Theory and Applications (Artech House, 1994) and Phased Array Antennas, Floquet Analysis, Synthesis, BFNs and Active Array Systems (John Wiley, 2006). He authored or coauthored more than 100 technical articles and five book chapters and has 25 issued patents. His technical interests include electromagnetics, printed antennas, multilayered structures, active phased arrays, and the modeling of microwave components and circuits.,Dr. Bhattacharyya became a Distinguished Lecturer at IEEE APS Society in 2011. He was a recipient of numerous awards, including the 1996 Hughes Technical Excellence Award, the 2002 Boeing Special Invention Award for his invention of “High-Efficiency horns,” the 2003 Boeing Satellite Systems Patent Awards, the 2005 Tim Hannemann Annual Quality Award, the 2007 Distinguished Engineer Award at Northrop Grumman Space Technology, and the 2020 Extraordinary Engineering and Technology Award at Lockheed Martin Space. He served as an Associate Editor for the IEEE Transactions Antennas and Propagation, from 2012 to 2016.

We look forward to seeing you there!