Speaker: Assoc. Prof. Özlem Özgün, Hacettepe University

Topic: "The Magic World of Transformation Electromagnetics: Invisibility and Beyond"

Location: Middle East Technical University, Ankara, Turkey

Abstract:  In recent years, the concept of Transformation Electromagnetics (TEM) (or Transformation Optics) has attracted a considerable interest because it led to the design of a wide variety of electromagnetic and optical devices, such as invisibility cloak, reshapers, concentrators, rotators, RCS reduction of radar targets, flat lenses, miniaturization of antennas and microwave devices, etc. TEM is an intuitive approach for designing application-oriented transformation media that can flexibly tune electromagnetic waves in a desired manner by using the form invariance property of Maxwell’s equations under coordinate transformations. The theoretical foundations of TEM are on very firm foundation, and they have never been challenged. However, the physical realization of such transformation media poses challenges because of spatial variations of the material specifications. There are some promising studies in the literature related to the practical realization of such materials, thanks to the advancements in the metamaterial technology. Without dealing with the physical implementation of such materials, the reshaping approach, which have developed in 2007 just after the introduction of invisibility cloak in 2006, inspired us to utilize TEM to circumvent certain computational difficulties arising in the numerical solution of complex electromagnetic problems. Therefore, we named such materials as software metamaterials, and employed them in the numerical solution of multi-scale electromagnetic problems, rough surface scattering and optimization problems in the context of finite element and finite difference time domain methods. In this talk, first the fundamentals of TEM will be reviewed to understand the basic physics behind it. Afterwards, an overview of the past and present applications of this approach will be presented.

Bio:  Dr. Özlem Özgün received her B.Sc. and M.Sc. degrees from Bilkent University, Ankara, Turkey in 1998 and 2000, respectively, and her Ph.D. degree from Middle East Technical University (METU), Ankara, Turkey in 2007, all in electrical and electronics engineering. She worked at Bilkent University as a teaching assistant during 1998-2000; at TÜBİTAK-İltaren during 2000-2004; at ASELSAN during 2004-2005; at Electromagnetic Communication Lab, Penn State University, USA as a postdoctoral researcher during 2007-2008; at METU Northern Cyprus Campus as an assistant professor during 2008-2012; and at TED University as an associate professor during 2012-2015. Currently, she is an associate professor in the electrical and electronics engineering department of Hacettepe University. Dr. Özgün’s research interests include computational electromagnetics, finite element method, domain decomposition methods, transformation electromagnetics, electromagnetic scattering, stochastic electromagnetic problems and optimization techniques. She has published over 100 refereed journal papers, book, book chapters, and conference articles. She received METU best Ph.D. thesis award in 2007, and the award for excellence in electromagnetics bestowed by Prof. Felsen Fund in 2009. She is a senior member of IEEE, and the secretary of the steering committee of URSI Turkey.

  Date and Time




  • Ankara, Ankara
  • Turkey



Assoc. Prof. Ozlem Ozgun


The Magic World of Transformation Electromagnetics: Invisibility and Beyond