Prof.Supriyo Bandyopadhyay

Antennas are the quintessential communication devices used to transmit and receive information encoded in electromagnetic waves. Their debilitating shortcoming is that they are resistant to miniaturization because their gain and efficiency plummet when they are shrunk to dimensions much smaller than the wavelength of the electromagnetic wave. The radiation efficiency, for instance, is limited to ~,A (radiating area)/ (lambda)E2 ,  where A is the radiating area of the antenna and l is the wavelength that is radiated. This is known as the Harrington limit.

We have recently invented and demonstrated a new genre of antennas that leverages magnetization precession or spin waves, induced in periodic arrays of nanomagnets by various types of external stimuli, to radiate electromagnetic waves in space. These unconventional antennas sport gain and intrinsic radiation efficiencies which can exceed the Harrington limit by as much as five orders of magnitude. We have investigated and demonstrated a large family of such antennas employing different systems such as multiferroic magnonic crystals, the spin Hall effect and topological insulators. These antennas have dimensions 3-4 orders of magnitude smaller than the wavelength, making antenna miniaturization possible. They can have embedded applications such as in medically implanted devices for acute care, stealth devices for defense and crime-fighting, and on-chip communication.

There are additional unusual features that these antennas exhibit. Despite being “point sources” that are  much smaller than the wavelength, these antennas do not radiate isotropically like a point source, but instead exhibit an anisotropic radiation pattern because of the inherent anisotropy of the spin waves that are the source of the electromagnetic radiation. One can steer the principal lobe of the radiated beam by manipulating the external stimuli, which enables active electronic scanning (AESA) without requiring a phased array. This talk will describe this new genre of nano-antennas.

Biography:

Supriyo Bandyopadhyay is the Commonwealth Professor of Electrical and Computer Engineering at Virginia Commonwealth University where he directs the Quantum Device Laboratory. Research in the laboratory has been frequently featured in national and international media (newspapers, internet blogs, magazines such as Business Week, journals such as Nature and Nanotechnology, TV networks such as CBS, radio such as NPR, and several internet news portals). The laboratory’s educational activities were featured in a pilot study conducted by the ASME at Penn State University. Prof. Bandyopadhyay has received many awards such as Virginia’s Outstanding Scientist from Virginia’s Governor Terence R. McAuliffe in 2016; Distinguished Alumnus award from his alma mater the Indian Institute of Technology, Kharagpur, India in 2016; the Distinguished Scholarship Award (given annually to one faculty member in his University) in 2012; and the University Award of Excellence (the highest honor his University can bestow on a faculty member, one per year) in 2017. His department gave him the Lifetime Achievement Award (one of two given in the department’s history). His earlier employer, University of Nebraska-Lincoln, conferred on him the College of Engineering Research Award (1998), the College of Engineering Service Award (2000) and the Interdisciplinary Research Award (2001) given jointly by the College of Engineering, the College of Science, and the Institute for Agricultural and Natural Resources. In 2018, he received the State Council of Higher Education for Virginia Outstanding Faculty Award which is the highest award for educators in private and public universities in the State of Virginia. In 2020 Dr. Bandyopadhyay received the “Pioneer in Nanotechnology” award from the Institute of Electrical and Electronics Engineers (IEEE). Prof. Bandyopadhyay has authored and co-authored over 400 research publications and presented over 150 invited talks and colloquia across six continents. He is currently a Sigma Xi Distinguished Lecturer who lectures globally on different topics related to spintronics. He has also authored/co-authored three classic textbooks (one of them the only English language textbook on spintronics until now) that have taught the field of spintronics and quantum device theory to tens of thousands of students across the world. Prof. Bandyopadhyay served as a Jefferson Science Fellow of the US National Academies of Science, Engineering and Medicine during 2020-2021 and was assigned as a Senior Adviser to the US Agency for International Development (USAID) Bureau for Europe and Eurasia, Division of Energy and Infrastructure. He also served as an “Expert” in the Engineering Directorate of the US National Science Foundation during 2023-2025. Prof. Bandyopadhyay is a Fellow of the Institute of Electrical and Electronics Engineers, the American Physical Society, the Electrochemical Society, the Institute of Physics (UK) and the American Association for the Advancement of Science.

Email:

Address:Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, VA , United States, 23284