Cairo University

MTPR Journal



Zewail City of Science and Technology
Vol./Issue: 16 , id: 190

The turn towards optical computers and photonic integrated circuits in high capacity optical networks has attracted the interests of expert researchers nowadays. This is because all optical packet switching and routing technologies hold promise to provide more efficient power and footprint scaling with increased router capacity. Therefore, it is aimed to integrate more optical processing elements into the same chip, and thus, increase on-chip processing capability and system intelligence. The merging of components and functionalities drives down packaging cost, bringing photonic devices one step (or more) closer to deployment in routing systems. Photonic crystal devices can be functionally used as a part of comprehensive all photonic crystal based system, where on the same photonic crystal platform, many functionalities can be realized. Therefore, photonic crystals have recently received much attention due to their unique properties in controlling the propagation of light. Many potential applications of photonic crystals require some capability for tuning through external stimuli. It is anticipated that the photonic crystals infiltrated with liquid crystals (LCs) have high tunability with external electric field and temperature. For the vast majority of LCs, the application of an electric field results in an orientation of the nematic director either parallel or perpendicular to the field, depending on the sign of the dielectric anisotropy of the nematic medium. `Plasmonics' is a relatively new term in Optics which refers to applications or phenomena in which surface plasmons (SP) are involved. Recently, the scientists and engineers of several disciplines have turned their attention to the plasmonic effects and their applications.This is because advances in technology have allowed fabrication and patterning of metallic structures in nanometer scale. Further, the SP waveguides can confine the light in nanoscale dimensions beyond the diffraction limit. Therefore, more compact optical systems can be developed based on the plasmonic waveguides. In almost all cases, an accurate quantitative theoretical modelling of these devices has to be based on advanced computational techniques that solve the corresponding, numerically very large linear, nonlinear or coupled partial differential equations. In this talk, the different computational modelling techniques will be introduced. In addition, novel designs of high birefringence LC PCF infiltrated with a nematic liquid crystal (NLC-PCF) are presented and analyzed. Moreover, due to their different uses in communication systems, the performance of novel designs of high tunable polarization rotator, directional coupler, polarization splitter, plasmonic multiplexer-demultiplexer, plasmonic temperature sensors based on the NLC-PCF will be introduced. The simulation results are obtained using full vectorial finite difference method, full vectorial finite difference beam propagation method, and finite element method (FEM) with nonuniform meshing capabilities and perfect matched layer boundary conditions.