284 citations · 1.1k across the 24 of their papers we have counts for
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Visualizing femtosecond dynamics with ultrafast electron probes through terahertz compression and time-stamping
Mohamed A. K. Othman, Emma C. Snively, Annika E. Gabriel +9
Visualizing ultrafast dynamics at the atomic scale requires time-resolved pump-probe characterization with femtosecond temporal resolution. For single-shot ultrafast electron diffr…
Theory of Coupled Resonator Optical Waveguides (CROW) Exhibiting High Order Exceptional Points of Degeneracy
Mohamed Y. Nada, Mohamed A. K. Othman, Filippo Capolino
We present a novel approach and a theoretical framework for generating high order exceptional points of degeneracy (EPD) in photonic structures based on periodic coupled resonators…
The degenerate band edge laser: a new paradigm for coherent light-matter interaction
Mehdi Veysi, Mohamed A. K. Othman, Alexander Figotin +1
We propose a novel class of lasers based on a fourth order exceptional point of degeneracy (EPD) referred to as the degenerate band edge (DBE). EPDs have been found in Parity-Time-…
Giant resonance and anomalous quality factor scaling in coupled resonator optical waveguides at the degenerate band edge
Mohamed Y. Nada, Mohamed A. K. Othman, Ozdal Boyraz +1
We propose a novel scheme for enhancing the quality factor of coupled resonators optical waveguides (CROWs) when operating near a degenerate band edge (DBE). A DBE is a four-mode e…
Exceptional points of degeneracy and -symmetry in photonic coupled chains of scatterers
Mohamed A. K. Othman, Vincenzo Galdi, Filippo Capolino
We demonstrate the existence of exceptional points of degeneracy (EPD) of periodic eigenstates in non-Hermitian coupled chains of dipolar scatterers. Guided modes supported by thes…
Theory of Exceptional Points of Degeneracy in Uniform Coupled-Waveguides and Balance of Gain and Loss
Mohamed A. K. Othman, Filippo Capolino
We present a transmission line theory of exceptional points of degeneracy (EPD) in coupled-mode guiding structures, i.e., a theory that illustrates the characteristics of coupled e…
Demonstration of a Degenerate Band Edge in Periodically-Loaded Circular Waveguides
Mohamed Othman, Filippo Capolino
We demonstrate the existence of a special degeneracy condition, called degenerate band edge (DBE), between two Bloch modes in periodically loaded circular all-metallic waveguides a…
Theory and New Amplification Regime in Periodic Multi Modal Slow Wave Structures with Degeneracy Interacting with an Electron Beam
Mohamed Othman, Venkata Ananth Tamma, Filippo Capolino
We present the theory of a new amplification regime in Travelling Wave Tubes (TWTs) composed of a slow-wave periodic structure that supports multiple electromagnetic modes that can…
Giant Gain Enhancement in Photonic Crystals with a Degenerate Band Edge
Mohamed Othman, Farshad Yazdi, Alex Figotin +1
We propose a new approach leading to giant gain enhancement. It is based on unconventional slow wave resonance associated to a degenerate band edge (DBE) in the dispersion diagram…
Thermal Hyperbolic Metamaterials
Yu Guo, Zubin Jacob
We explore the near-field radiative thermal energy transfer properties of hyperbolic metamaterials. The presence of unique electromagnetic states in a broad bandwidth leads to supe…