Dr. Mohamed A. Salem

X-waves are a class of Localized Wave solutions to the wave equation; they can propagate indefinitely without distortion while maintaining their localization in space. These localized propagation characteristics have made them a focus of research interest in acoustics, electromagnetics, and optics. In this presentation, the theoretical development of full-vector electromagnetic X-Waves will be outlined. This rather novel form of X-waves is obtained from a weighted superposition of transverse electric and magnetic polarized field components. These polarized field components are constructed by non-monochromatic superposition of Bessel beams with unique spectral characteristics. In this formulation, the complex weights of the polarized field components can be used to locally control the signs of all components of the Poynting vector of the full-vector X-Wave. Certain combinations of these weights result in negative energy flux density in the direction of propagation in a bounded region around the peak of the X-Wave; in this region the local behavior of the wave is similar to that of a wave, which propagates in a left-handed (meta-material) medium. In the study of the behavior of full-vector X-Waves at different planar interfaces, changes in the field shape and intensity were observed in the reflected and transmitted waves. Also, a novel longitudinal shift (in the direction of propagation) is observed when full-vector X-Waves pass through a dielectric slab under frustrated total reflection condition. These peculiar characteristics of the full-vector X-Waves could be used to improve the performance of electromagnetic and optical traps and tweezers, where the location and momentum of micro- and nano-particles are manipulated by changing the Poynting vector. Other interesting applications of X-waves in electromagnetics and optics include the generation of tractor beams and the detection of transformation electromagnetics based invisibility cloaks.

Biography: Mohamed A. Salem was born in Cairo, Egypt. He received his B.E. and M.E. degrees in Electrical Engineering, and a Ph.D. degree in Applied Mathematics from Ain Shams University, Cairo, Egypt in 2001, 2004, and 2008, respectively. He received a Ph.D degree in Electrical Engineering from New Jersey Institute of Technology (NJIT), NJ in 2009. From September 2005 to August 2009, he was offered a teaching assistant award by NJIT as an enrolled Ph.D. student. From March 2010 to March 2013, he was a Postdoctoral Fellow at the Computational Electromagnetics Laboratory at King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia. He was the recipient of the Young Scientist Award of URSI-GASSS 2011, Istanbul, Turkey and EMTS 2013, Hiroshima, Japan. Since April 2013, he joined the research group of Professor Christophe Caloz at École Polytechnique de Montréal, Canada, as a Postdoctoral Fellow. His current research interests include wave propagation and scattering phenomena, novel approaches to electromagnetic field manipulation using meta surfaces and materials, and the generation of propagation-invariant and non-conventional wave fields, such as vortex and accelerated beams.

Address:New Jersey, United States

Dr. Mohamed A. Salem

Biography:

Address:New Jersey, United States

Dr. Mohamed A. Salem

Biography:

Address:New Jersey, United States