Thursday, February 28, 2013

Seminar Today: "Transmission Anomalies in Dielectric and Metallic Photonic Crystals" by Stephanos Venakides / 2.28.13 / 12:00-1:00pm / CREOL 102


"Transmission Anomalies in Dielectric and Metallic Photonic Crystals" by Stephanos Venakides
Thursday, February 28th, 2013 from 12:00-1:00pm
CREOL Room 102


Stephanos Venakides, Duke University
Joint work with Stephen Shipman, LSU

Abstract:
We describe the transmission anomalies that we observed numerically in the electromagnetic transmission coefficient of dielectric and metallic photonic crystal (PC) slabs or films and we present an asymptotic formula for the resonant enhancement. Central to calculating the transmission anomalies is the perturbation of three coincident zeros-those of the dispersion relation for slab modes, the reflection constant, and the transmission constant. On the spectral side, the eigenvalue which corresponds to a guided mode is perturbed off its imbedded position on the real axis and turns into a resonance. The theory applies to very general geometries of the unit cell.  In the particular case of extraordinary transmission (EOT) in a periodically perforated metallic PC films, we take into account the geometry and pinpoint the resonance with great precision near the frequency of the first Raleigh anomaly in a combined analytic/numerical approach.  Furthermore, we demonstrate that a thin transmission spike observed in simulations is not seen in experiments because of  imperfectly collimated incident beams.

Biography:
Stephanos Venakides is a Professor of Mathematics at Duke University. He received his Ph.D. from the Courant Institute of Mathematical Sciences in 1982, after graduating from the School of Electrical and Mechanical Engineering of the University of Athens (Greece) in 1969, subsequently working as an engineer in the industry for seven years and receiving an M.S degree in applied mathematics from Georgia Tech in 1979. In 1982, he joined the faculty of the Department of Mathematics at  Stanford University as assistant professor and moved to  Duke University in 1986, first as associate professor and since 1991 as professor. His research interests include partial differential equations and  integrable systems, linear and nonlinear optics and the analysis of coherent structures in optical systems,  electromagnetics in general, quantum physics and polaritons, as well as the investigation of the  forces of morphogenesis in biology. In 2005 he gave one of the three Abel lectures at the award of the Abel Prize to Peter D. Lax, by the Royal Academy of Norway in Oslo. 

For more information:
Dr. Bahaa Saleh
Dean & Director, Professor of Optics
407-823-6834

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