The Department of Physics is delighted to welcome Professor Nader Engheta (University of Pennsylvania) as a Colloquium Speaker for the academic year 2025/26. Please join us to listen to Professor Engheta's seminar.
A reception will be held directly after the seminar, where tea and coffee will be provided.
The seminar is open to anyone from the university, students are encouraged to attend.
Title
Near-Zero-Index Optics
Abstract
Materials are often used to manipulate and control photons. Metamaterials -- judiciously engineered material structures -- have enabled scientists and engineers to construct platforms with unconventional material parameters, providing exciting opportunities for optical and microwave devices and components. One major platform of metamaterials is the near-zero-index metamaterials. In such structures, the effective relative permittivity and/or relative permeability are designed to be near zero at operating frequencies, resulting in an effective refractive index close to zero. Consequently, in such epsilon-near-zero (ENZ), mu-near-zero (MNZ), and/or near-zero-index (NZI) structures, the wavelength is “stretched”, and therefore the phase distribution is effectively uniform throughout this volume. This leads to a variety of unique features in wave physics, including supercoupling, photonic doping, photonic surface states, electric levitation, extreme quantum optics, thermal beaming, and giant nonlinearity, just to name a few. In this talk, I will present an overview of the fundamental principles and the unique physics and engineering of wave interaction with near-zero-index structures. I will then discuss some of the applications of such platforms in photonics and microwave technologies. Possible future directions of research in this field will also be forecasted.
Bio
Nader Engheta is the H. Nedwill Ramsey Professor at the University of Pennsylvania in Philadelphia, with affiliations in the Departments of Electrical and Systems Engineering, Physics and Astronomy, Bioengineering, and Materials Science and Engineering. He received his BS degree from the University of Tehran and his MS and Ph.D. degrees from Caltech. His current research activities span a broad range of areas, including metamaterials, optics, electrodynamics, microwaves, photonics, nano-optics, graphene photonics, imaging, and sensing inspired by the eyes of animal species, microwave and optical antennas, and physics and engineering of fields and waves.
Elected to the US National Academy of Engineering (NAE), American Academy of Arts and Sciences (AAA&S), Academia Europaea (The Academy of Europe, AE), and the Canadian Academy of Engineering (CAE), Nader has received several awards for his research, including the Isaac Newton Medal from the Institute of Physics (UK), the Benjamin Franklin Medal from the Franklin Institute, the Max Born Award from the OPTICA (formerly Optical Society), the Caltech Distinguished Alumni Award, the Rolf Landauer Medal, the IEEE Pioneer Award in Nanotechnology, the SPIE Gold Medal, the Balthasar van der Pol Gold Medal from the International Union of Radio Science (URSI), the IEEE Electromagnetics Award, the Vannevar Bush Faculty Fellowship Award from DoD, 2006 Scientific American Magazine 50 Leaders in Science and Technology, and the Guggenheim Fellowship.
He is a Fellow of nine international scientific and technical organizations, i.e., APS, OPTICA, MRS, SPIE, IEEE, URSI, AAAS, IOP (UK), and US National Academy of Inventors (NAI). He received honorary doctoral degrees from Aalto University in Finland in 2016, the University of Stuttgart, Germany, in 2016, and Ukraine’s National Technical University Kharkiv Polytechnic Institute in 2017.