Localized surface plasmons (LSPs) are a potentially valuable property for the practical use of sm... more Localized surface plasmons (LSPs) are a potentially valuable property for the practical use of small size metallic particles. Exploiting the LSPs in metallic nanoparticle (NP)-based solar cells was shown to increase the efficiency of solar panels. A large extinction cross section of NPs allows for high scattering of light at the surface of the panel, which reduces the panel thickness, allowing for small size and low-cost solar cells. In this paper, the extinction cross-section of spherical nanoparticles is studied and simulated numerically. Surface plasmons were first modeled using the Drude’s model then the scattering and absorption cross-sections were derived. Commercial3D simulation software was used to model the near field distribution of the three NP structures. A spherical nanoparticle made of silver was modeled first and the field distribution inside the sphere was presented. The extinction cross-section was also calculated. Two other structures were also presented; a silic...
In this study, Four Wave Mixing (FWM) characteristics in photonic crystal fibers are investigated... more In this study, Four Wave Mixing (FWM) characteristics in photonic crystal fibers are investigated. The effect of channel spacing, phase mismatching, and fiber length on FWM efficiency have been studied. The variation of idler frequency which obtained by this technique with pumping and signal wavelengths has been discussed. The effect of fiber dispersion has been taken into account; we obtain that the influence of FWM can be reduced by irregular channel spacing. We use three wavelengths in the calculations (580, 780, and 1040nm) which are the zero dispersion wavelengths, all the results reported in this work are simulated using MATLAB 7. :ةــــــصلاخلا ددزا لا ام دار زف نات ةاسارد مات ثافم ةاحروةبلا ةفاوايلا لتافليا ياف تاجوم عبرأ جمد ةسارد مت ,ثحبلا اذه يف ةاسارد مات دلذار و تاجوملا جامد د تافر اةع مذخ سملا ففةلا لوط و تجوملا روط قبتطت مذع , تجوملا فب دصتفلا لا هذه م ةجتتنلا ةجوملا ددزت يف زفغ لا زظنب ذخيا عم دزش نملا ةجومةل و خيلا رذصمل يجوملا لوطلا م در عم ةفنق ( يه و تبتسحلا يف ة...
Supercontinuum generation (SCG) is the production of continuous spectral broadening. Efficient SC... more Supercontinuum generation (SCG) is the production of continuous spectral broadening. Efficient SCG is affected by the group velocity dispersion (GVD), nonlinear characteristics, waveguide geometrical parameters, and pump wavelength. Photonic crystal fibers (PCFs) offer promising advantages over standard fibers such as desirable dispersion properties and controllable mode area. Silicon (Si) is known for its large refractive index which enhances the nonlinear effect in silicon waveguides. The promising properties of silicon is combined with the strong characteristics of photonic crystals in a silicon-core PCF to broaden the spectrum. The effect of varying the pump power, and input pulse wavelength on the broadening bandwidth is studied. The modal characteristics of the reported PCF are calculated using full vectorial finite element method (FV-FEM) with perfectly matching layers (PML) boundary conditions. In this investigation, the effective mode index, dispersion profile of the fundam...
IOP Conference Series: Materials Science and Engineering, 2019
In this work, the determination of the masses of supermassive black holes (SMBHs) and the propert... more In this work, the determination of the masses of supermassive black holes (SMBHs) and the properties of their host spiral galaxies are focused for the purposes of constraining scaling relations and with the aim of understanding the role of SMBHs in the evolution of galaxies. The measurements of SMBHs mass for a sample of 40 spiral galaxies were studied by applying indirect techniques (the SMBHs mass versus stellar/gas velocity dispersion relation). In addition, spiral arm pitch angle of a sample of nearly face-on spiral galaxies were measured using IRAF (The Image Reduction and Analysis Facility) and two-dimensional Fast Fourier Transform (2DFFT) program. Finally, we present a new correlation between spiral arm pitch angle (a measure of the tightness of spiral structure) and the mass of supermassive black holes (BHs) in the nuclei of classical galaxies.
Applied Computational Electromagnetics Society Journal
An ultra-compact polarization splitter based on dual core nematic liquid crystal silica photonic ... more An ultra-compact polarization splitter based on dual core nematic liquid crystal silica photonic crystal fiber (NLC-PCF) is proposed and analyzed. The refractive index difference between the NLC and silica material guaranties the index guiding through the reported splitter. The dual core NLC-PCF has strong polarization dependence due to the birefringence between the two polarized modes. The coupling characteristics of the proposed design are studied thoroughly using full vectorial fine difference method (FV-FDM) and the propagation analysis is performed by full vectorial finite difference beam propagation method (FVFD-BPM). The numerical results reveal that the reported splitter has short device length of 482µm with low crosstalk better than -20 dB with wide bandwidths of 31.5 nm and 19 nm for the quasi TE and quasi TM modes, respectively. The compact coupling lengths as well as the low crosstalks over reasonable bandwidths are the main advantages of the reported dual core NLC-PCF.
An ultra-compact polarization splitter based on dual core nematic liquid crystal silica photonic ... more An ultra-compact polarization splitter based on dual core nematic liquid crystal silica photonic crystal fiber (NLC-PCF) is proposed and analyzed. The refractive index difference between the NLC and silica material guaranties the index guiding through the reported splitter. The dual core NLC-PCF has strong polarization dependence due to the birefringence between the two polarized modes. The coupling characteristics of the proposed design are studied thoroughly using full vectorial fine difference method (FV-FDM) and the propagation analysis is performed by full vectorial finite difference beam propagation method (FVFD-BPM). The numerical results reveal that the reported splitter has short device length of 482 µm with low crosstalk better than -20 dB with wide bandwidths of 31.5 nm and 19 nm for the quasi TE and quasi TM modes, respectively. The compact coupling lengths as well as the low crosstalks over reasonable bandwidths are the main advantages of the reported dual core NLC-PCF.
Highly birefringent photonic crystal fiber (PCF) is proposed and analyzed using full vectorial fi... more Highly birefringent photonic crystal fiber (PCF) is proposed and analyzed using full vectorial finite element method. The reported design has a central large core filled with nematic liquid crystal (NLC) which provides tunability with the external electric field and temperature. In addition, the full permittivity tensor of the NLC material is taken into account when we study the modal properties of the proposed PCF. The effects of the geometrical parameters, rotation angle of the director of the NLC, and temperature on the modal properties of the reported design are investigated. The suggested design offers high birefringence of 0.191 at the operating wavelength of 1.55 μm with NLC diameter of 3.4 μm with low losses of the two polarized modes. As the NLC diameter decreases to 1.0 μm, high birefringence of 0.08 is obtained with single mode NLC PCF design, which is significantly large birefringence to maintain polarization state.
Localized surface plasmons (LSPs) are a potentially valuable property for the practical use of sm... more Localized surface plasmons (LSPs) are a potentially valuable property for the practical use of small size metallic particles. Exploiting the LSPs in metallic nanoparticle (NP)-based solar cells was shown to increase the efficiency of solar panels. A large extinction cross section of NPs allows for high scattering of light at the surface of the panel, which reduces the panel thickness, allowing for small size and low-cost solar cells. In this paper, the extinction cross-section of spherical nanoparticles is studied and simulated numerically. Surface plasmons were first modeled using the Drude’s model then the scattering and absorption cross-sections were derived. Commercial3D simulation software was used to model the near field distribution of the three NP structures. A spherical nanoparticle made of silver was modeled first and the field distribution inside the sphere was presented. The extinction cross-section was also calculated. Two other structures were also presented; a silic...
In this study, Four Wave Mixing (FWM) characteristics in photonic crystal fibers are investigated... more In this study, Four Wave Mixing (FWM) characteristics in photonic crystal fibers are investigated. The effect of channel spacing, phase mismatching, and fiber length on FWM efficiency have been studied. The variation of idler frequency which obtained by this technique with pumping and signal wavelengths has been discussed. The effect of fiber dispersion has been taken into account; we obtain that the influence of FWM can be reduced by irregular channel spacing. We use three wavelengths in the calculations (580, 780, and 1040nm) which are the zero dispersion wavelengths, all the results reported in this work are simulated using MATLAB 7. :ةــــــصلاخلا ددزا لا ام دار زف نات ةاسارد مات ثافم ةاحروةبلا ةفاوايلا لتافليا ياف تاجوم عبرأ جمد ةسارد مت ,ثحبلا اذه يف ةاسارد مات دلذار و تاجوملا جامد د تافر اةع مذخ سملا ففةلا لوط و تجوملا روط قبتطت مذع , تجوملا فب دصتفلا لا هذه م ةجتتنلا ةجوملا ددزت يف زفغ لا زظنب ذخيا عم دزش نملا ةجومةل و خيلا رذصمل يجوملا لوطلا م در عم ةفنق ( يه و تبتسحلا يف ة...
Supercontinuum generation (SCG) is the production of continuous spectral broadening. Efficient SC... more Supercontinuum generation (SCG) is the production of continuous spectral broadening. Efficient SCG is affected by the group velocity dispersion (GVD), nonlinear characteristics, waveguide geometrical parameters, and pump wavelength. Photonic crystal fibers (PCFs) offer promising advantages over standard fibers such as desirable dispersion properties and controllable mode area. Silicon (Si) is known for its large refractive index which enhances the nonlinear effect in silicon waveguides. The promising properties of silicon is combined with the strong characteristics of photonic crystals in a silicon-core PCF to broaden the spectrum. The effect of varying the pump power, and input pulse wavelength on the broadening bandwidth is studied. The modal characteristics of the reported PCF are calculated using full vectorial finite element method (FV-FEM) with perfectly matching layers (PML) boundary conditions. In this investigation, the effective mode index, dispersion profile of the fundam...
IOP Conference Series: Materials Science and Engineering, 2019
In this work, the determination of the masses of supermassive black holes (SMBHs) and the propert... more In this work, the determination of the masses of supermassive black holes (SMBHs) and the properties of their host spiral galaxies are focused for the purposes of constraining scaling relations and with the aim of understanding the role of SMBHs in the evolution of galaxies. The measurements of SMBHs mass for a sample of 40 spiral galaxies were studied by applying indirect techniques (the SMBHs mass versus stellar/gas velocity dispersion relation). In addition, spiral arm pitch angle of a sample of nearly face-on spiral galaxies were measured using IRAF (The Image Reduction and Analysis Facility) and two-dimensional Fast Fourier Transform (2DFFT) program. Finally, we present a new correlation between spiral arm pitch angle (a measure of the tightness of spiral structure) and the mass of supermassive black holes (BHs) in the nuclei of classical galaxies.
Applied Computational Electromagnetics Society Journal
An ultra-compact polarization splitter based on dual core nematic liquid crystal silica photonic ... more An ultra-compact polarization splitter based on dual core nematic liquid crystal silica photonic crystal fiber (NLC-PCF) is proposed and analyzed. The refractive index difference between the NLC and silica material guaranties the index guiding through the reported splitter. The dual core NLC-PCF has strong polarization dependence due to the birefringence between the two polarized modes. The coupling characteristics of the proposed design are studied thoroughly using full vectorial fine difference method (FV-FDM) and the propagation analysis is performed by full vectorial finite difference beam propagation method (FVFD-BPM). The numerical results reveal that the reported splitter has short device length of 482µm with low crosstalk better than -20 dB with wide bandwidths of 31.5 nm and 19 nm for the quasi TE and quasi TM modes, respectively. The compact coupling lengths as well as the low crosstalks over reasonable bandwidths are the main advantages of the reported dual core NLC-PCF.
An ultra-compact polarization splitter based on dual core nematic liquid crystal silica photonic ... more An ultra-compact polarization splitter based on dual core nematic liquid crystal silica photonic crystal fiber (NLC-PCF) is proposed and analyzed. The refractive index difference between the NLC and silica material guaranties the index guiding through the reported splitter. The dual core NLC-PCF has strong polarization dependence due to the birefringence between the two polarized modes. The coupling characteristics of the proposed design are studied thoroughly using full vectorial fine difference method (FV-FDM) and the propagation analysis is performed by full vectorial finite difference beam propagation method (FVFD-BPM). The numerical results reveal that the reported splitter has short device length of 482 µm with low crosstalk better than -20 dB with wide bandwidths of 31.5 nm and 19 nm for the quasi TE and quasi TM modes, respectively. The compact coupling lengths as well as the low crosstalks over reasonable bandwidths are the main advantages of the reported dual core NLC-PCF.
Highly birefringent photonic crystal fiber (PCF) is proposed and analyzed using full vectorial fi... more Highly birefringent photonic crystal fiber (PCF) is proposed and analyzed using full vectorial finite element method. The reported design has a central large core filled with nematic liquid crystal (NLC) which provides tunability with the external electric field and temperature. In addition, the full permittivity tensor of the NLC material is taken into account when we study the modal properties of the proposed PCF. The effects of the geometrical parameters, rotation angle of the director of the NLC, and temperature on the modal properties of the reported design are investigated. The suggested design offers high birefringence of 0.191 at the operating wavelength of 1.55 μm with NLC diameter of 3.4 μm with low losses of the two polarized modes. As the NLC diameter decreases to 1.0 μm, high birefringence of 0.08 is obtained with single mode NLC PCF design, which is significantly large birefringence to maintain polarization state.
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Papers by Rasha A . Hussein