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Heikal A.M.,Center for Photonics and Smart Materials | Heikal A.M.,University of South Wales | Hameed M.F.O.,Center for Photonics and Smart Materials | Hameed M.F.O.,Mansoura University | Obayya S.S.A.,Center for Photonics and Smart Materials
Journal of Lightwave Technology | Year: 2013

In this paper, the modal analysis of a novel design of three trenched single mode channel plasmon polariton is introduced and analyzed using the full-vectorial finite difference method for linear oblique and curved interfaces (FVFD-LOCI). The analyzed parameters are the real effective index, propagation length, and lateral mode radius r3dB. In addition, the figure of merit (FOM) defined as the ratio between propagation length and lateral mode radius is also studied. The analysis is performed for different channel plasmon polariton (CPP) waveguides; trenched-groove, V-groove and the suggested three trenched structure over a specific spectral range (200-550 THz). The selected band of frequency is chosen to ensure the existence of the CPP fundamental mode. The reported design offers very high FOM at low frequency band (200-350 THz) compared to the well known V-groove structure. However, the lateral mode radius r3dB of the suggested three trenched structure is slightly smaller than that of the V-groove structure. For high frequency band (350-550 THz), the FOM is still higher than that of the V-groove structure while the lateral mode radius r3dB is slightly greater than that of the V-groove structure. © 1983-2012 IEEE.


Ayad M.A.,American University in Cairo | Obayya S.S.A.,Center for Photonics and Smart Materials | Swillam M.A.,American University in Cairo
Journal of Lightwave Technology | Year: 2014

A novel design of a submicron power splitter is presented using plasmonics with the metal insulator metal (MIM) configuration. A simple analytical model is utilized to obtain good initial design. The final optimized design is obtained using finite-difference time domain based optimization. The proposed approach provides a simple and efficient methodology for designing 1xN power splitters using MIM configuration. The proposed power splitters are ultra wide band(~ 2 μm) with negligible imbalance. The approach is utilized to design up to 1 × 4, 1 × 8, and 1 × 16 integrated power splitters with submicron footprint, where all the optimized designs are validated. © 1983-2012 IEEE.


Hameed M.F.O.,Mansoura University | Hameed M.F.O.,Center for Photonics and Smart Materials | Obayya S.S.A.,Center for Photonics and Smart Materials
Optics Letters | Year: 2014

In this Letter, an ultra-compact polarization rotator (PR) based on silica photonic crystal fiber with liquid crystal core is introduced and analyzed using full-vectorial finite difference approaches. The analyzed parameters of the suggested PR are the conversion length, modal hybridness, power conversion and crosstalk. In addition, the fabrication tolerance analysis of the reported design is investigated in detail. The proposed PR has an ultra-compact device length of 4.085 μm and an almost 100% polarization conversion ratio. © 2014 Optical Society of America.


Hameed M.F.O.,Center for Photonics and Smart Materials | Hameed M.F.O.,Mansoura University | Heikal A.M.,Center for Photonics and Smart Materials | Heikal A.M.,Mansoura University | And 4 more authors.
Optics Express | Year: 2015

A novel ultra-high tunable photonic crystal fiber (PCF) polarization filter is proposed and analyzed using finite element method. The suggested design has a central hole infiltrated with a nematic liquid crystal (NLC) that offers high tunability with temperature and external electric field. Moreover, the PCF is selectively filled with metal wires into cladding air holes. Results show that the resonance losses and wavelengths are different in x and y polarized directions depending on the rotation angle of the NLC. The reported filter of compact device length 0.5 mm can achieve 600 dB/cm resonance losses at = 90° for x-polarized mode at communication wavelength of 1300 mm with low losses of 0.00751 dB/cm for y-polarized mode. However, resonance losses of 157.71 dB/cm at = 0° can be achieved for y-polarized mode at the same wavelength with low losses of 0.092 dB/cm for x-polarized mode. © 2015 OSA.


Azzam S.I.,Center for Photonics and Smart Materials | Azzam S.I.,Mansoura University | Obayya S.S.A.,Center for Photonics and Smart Materials
Optics Letters | Year: 2015

We investigate the polarization-dependent resonance tunneling effect in silicon waveguides to achieve ultracompact and highly efficient polarization fitters for integrated silicon photonics, to the best of our knowledge for the first time. We hence propose simple structures for silicon-on-insulator transverse electric (TE)-pass and transverse magnetic (TM)-pass polarizers based on the resonance tunneling effect in silicon waveguides. The suggested TE-pass polarizer has insertion losses (IL), extinction ratio (ER), and return losses (RL) of 0.004 dB, 18 dB, and 24 dB, respectively; whereas, the TM-pass polarizer is characterized by IL, ER, and RL of 0.15 dB, 20 dB, and 23 dB, respectively. Both polarizers have an ultra-short device length of only 1.35 and 1.31 μm for the TE-pass and the TM-pass polarizers which are the shortest reported lengths to the best of our knowledge. © 2015 Optical Society of America.


Younis R.M.,Mansoura University | Areed N.F.F.,Mansoura University | Areed N.F.F.,Center for Photonics and Smart Materials | Obayya S.S.A.,Center for Photonics and Smart Materials
IEEE Photonics Technology Letters | Year: 2014

We propose two novel designs of compact, linear, and all-optical OR and AND logic gates based on photonic crystal architecture. The proposed devices are formed by the combination of the ring cavities and Y-shape line defect coupler placed between two waveguides. The performance of the proposed logic gates has been analyzed and investigated using finite difference time domain method. The suggested design for AND gate offers ON to OFF logic level contrast ratio of not less than 6 dB and the suggested design for OR gate offers transmitted power of not less than 0.5. On top of that, the proposed OR and AND logic gates can operate at bit rates of around 0.5 and 0.208 Tb/s, respectively. Further, the calculated fabrication tolerances of the suggested devices show that the rods radii of the ring cavities need to be controlled with no more than ±10% and ±3% fabrication errors for optical OR and AND gates, respectively. It is expected that such designs have the potential to be key components for future photonic integrated circuits due to their simplicity and small size. © 2014 IEEE.


Azzam S.I.,Center for Photonics and Smart Materials | Obayya S.A.,Mansoura University
Signal Processing in Photonic Communications, SPPCom 2015 | Year: 2015

A theoretical study of plasmonic effects in silicon nanostructures is introduced. It is found that silicon exhibit metal-like properties at the edge of UV/VIS spectrum allowing silicon nanostructures to support surface plasmon modes. © 2015 OSA.


Hameed M.F.O.,Mansoura University | Heikal A.M.,Center for Photonics and Smart Materials | Obayya S.S.A.,Center for Photonics and Smart Materials
IEEE Photonics Technology Letters | Year: 2013

In this letter, a novel design of a passive ultra-compact polarization rotator based on soft glass equiangular spiral photonic crystal fiber (ES-PCF) is proposed and analyzed using full vectorial finite difference approaches. The suggested ES-PCF has eight arms with a central elliptical air hole, which can be shifted in $x$ and $y$ directions to achieve complete polarization conversion. In addition, the major axis of the elliptical hole is rotated by 45°, which offers 99% polarization conversion ratio with ultra-compact device length of 96 μ m. It is also evident from the numerical results that the polarization rotation would be more than 98% over the 1.5-1.6 μm wavelength range. © 1989-2012 IEEE.


Areed N.F.F.,Mansoura University | Obayya S.S.A.,Center for Photonics and Smart Materials
IEEE Photonics Technology Letters | Year: 2013

A novel design of an easily and fully integrated terabit per second (Tbit/s) optical router is presented and analyzed using the finite difference time domain method. The proposed router consists of three photonic bandgap (PBG) waveguides with two nematic liquid crystal (NLC) layers. The suggested device can be used to divert the light beam to one of the three photonic crystal waveguides based on the biasing states of the two NLC layers. In this way, there are three different modes of operation where each one is used for routing data to the required direction. The suggested device offers crosstalk of 19 dB. In addition, the reported structure opens up the revenue for building multi-port optical routers through the use of a number of appropriately positioned NLC layers within the platform of PBG structure. © 1989-2012 IEEE.


Said A.M.A.,Center for Photonics and Smart Materials | Obayya S.S.A.,Center for Photonics and Smart Materials
Optical and Quantum Electronics | Year: 2015

Blocked Schur finite-element bidirectional beam propagation method (BS-FE-BiBPM) is introduced for the solution of electron waveguides with multiple discontinuities. Scattering properties could be accurately calculated using BiBPM based on time-independent Schrödinger equation while Blocked Schur algorithm is used for accurate computation of the characteristic matrix square root. The suggested approach substantially reduces the computational time while preserving very high efficiency. © 2014, Springer Science+Business Media New York.

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