Data and Time November 6, 2009, 3:00-4:15 PM
Location Sanford Flemming Building (SF), Room B560
Host Leon Yuan

Complex Modes in Lossless Reciprocal Structures

Rubaiyat Islam

The Edward S. Rogers Sr. Department of Electrical and Computer Engineering (Electromagnetics)


In elementary Electromagnetics, we are introduced to propagating and attenuating guided waves in lossless media. In lossy media, we are aware of the existence of modes with complex propagation constants (decaying sinusoids). Less well known are perhaps the so called Complex modes which exhibit both attenuation and phase progression along lossless guides. They are found in a variety of structures including the Metamaterial negative-index slab in positive-index space and metallic slab guides for nano-photonic applications.

The purpose of this talk is to introduce the audience to the strange features of these modes and discuss some of the incorrect theoretical ideas about them which have been propagated since their discovery 50 years ago. The independent existence/excitation of a single complex mode (without its closely related conjugate counterpart) will be addressed and results will be presented to support our understanding that, contrary to existing theory, each complex mode in a conjugate pair is practically independent.


Rubaiyat Islam obtained his B.A.Sc. in Engineering Science (Elec. Option) from the University of Toronto in 2002. He is currently in the final year of this PhD under the supervision of Prof. G. V. Eleftheriades. His research interests include RF/Microwave passive devices (couplers, diplexers, filters ... etc), Metamaterials, EM theory and passive Network theory.