Science Publishing Group: American Journal of Optics and Photonics: Table of Contents
<i> American Journal of Optics and Photonics (AJOP) </i> is aimed to stimulate study and research in fundamental and applied science related to the problems in optics and photonics. Photonics integrates quantum electronics and optics to accelerate progress in the generation of novel photon sources and in their utilization in emerging applications at the micro and nano scales spanning from the far-infrared/THz to the x-ray region of the electromagnetic spectrum.AJOP welcome original contributions addressing issues ranging from fundamental understanding to emerging technologies and applications.
http://www.sciencepublishinggroup.com/j/ajop Science Publishing Group: American Journal of Optics and Photonics: Table of Contents
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American Journal of Optics and Photonics
American Journal of Optics and Photonics
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Simulation Study of Optical Transmission Properties of ZnO Thin Film Deposited on Dif-ferent Substrates
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20130101.11
ZnO is an important II-VI semiconductor material for devices with possible applications such as piezoelectric transducers, gas sensors, transparent electronic in solar cell, saw devices. Based on known research, ZnO is the most prom-ising in optoelectronic and optical applications, especially in UV region. An understanding of the optical properties of ZnO thin film on different substrates is also needed to obtain the optimal configuration for the best performance. In this work, we start our simulation by made a Matlab code to study the Sellmeier equation. The behavior of light transmission of ZnO/BK7 glass and ZnO/Sapphire is studied. Both the variation of thickness of ZnO film and different parameters of Sellmeier model are studied. This approach helps us to determine the best configuration (thin film / substrate) to made advices for optoelectronic applications.
ZnO is an important II-VI semiconductor material for devices with possible applications such as piezoelectric transducers, gas sensors, transparent electronic in solar cell, saw devices. Based on known research, ZnO is the most prom-ising in optoelectronic and optical applications, especially in UV region. An understanding of the optical properties of ZnO thin film on different substrates is also needed to obtain the optimal configuration for the best performance. In this work, we start our simulation by made a Matlab code to study the Sellmeier equation. The behavior of light transmission of ZnO/BK7 glass and ZnO/Sapphire is studied. Both the variation of thickness of ZnO film and different parameters of Sellmeier model are studied. This approach helps us to determine the best configuration (thin film / substrate) to made advices for optoelectronic applications.
Simulation Study of Optical Transmission Properties of ZnO Thin Film Deposited on Dif-ferent Substrates
doi:10.11648/j.ajop.20130101.11
American Journal of Optics and Photonics
2014-01-01
© Science Publishing Group
N. Bouchenak Khelladi
N. E. Chabane Sari
Simulation Study of Optical Transmission Properties of ZnO Thin Film Deposited on Dif-ferent Substrates
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© Science Publishing Group
Dynamics of Soliton Pulse Inside Optical Fiber
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The main aim of this paper is to implement the combine effect of linearity and nonlinearity in optical fiber that generate a stable, undistorted pulse called “soliton”. Analysis of first, second and third order soliton pulse propagation are done by modifying the nonlinear Schrodinger equation (NLSE).Further we have found that power requirement for transmitting fundamental order soliton, second order and third order are 83.3mW, 333.3mW and 750mW respectively. In which power of 83.3mW is appropriate for soliton pulse to maintain least loss during the propagation in optical fiber.
The main aim of this paper is to implement the combine effect of linearity and nonlinearity in optical fiber that generate a stable, undistorted pulse called “soliton”. Analysis of first, second and third order soliton pulse propagation are done by modifying the nonlinear Schrodinger equation (NLSE).Further we have found that power requirement for transmitting fundamental order soliton, second order and third order are 83.3mW, 333.3mW and 750mW respectively. In which power of 83.3mW is appropriate for soliton pulse to maintain least loss during the propagation in optical fiber.
Dynamics of Soliton Pulse Inside Optical Fiber
doi:10.11648/j.ajop.20130102.11
American Journal of Optics and Photonics
2014-01-01
© Science Publishing Group
Chakresh kumar
Rahul Kumar
Deepjyoti Das
Dynamics of Soliton Pulse Inside Optical Fiber
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http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20130102.11
© Science Publishing Group
Air-Holes Radius Change Effects and Structure Transitions in the Linear Photonic Crystal Nanocavities
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The strong localization of electromagnetic modes in high-Q/Vm (quality factor/modal volume) photonic crystal (PhC) nanocavities (NCs) makes them strong candidates for enhanced optical nonlinear effects, such as cavity quantum electrodynamics (QED) phenomena. These applications require precise control of cavity resonances mode. The cavity resonance is strongly depending on the lattice constant, a, and the air-hole radius, r, of photonic crystals. Slight modifications in the geometries of the photonic crystals will result in large differences in the dispersion characteristics. In this paper, by using BandSOLVE and FullWAVE software of RSoft Photonics CAD package, at first L1, L3 and L5 NCs in a semiconductor slab have been simulated in a hexagonal lattice of air-holes (radius r) with lattice constant a=270 nm and constant fill factor (r/a=0.29). Then, with radius reduction of the two ends air-holes (TEA-H), different confinement characteristics of photonic modes such as: numbers of confined modes, wavelengths, quality factors and two dimensional field profiles have been investigated. Calculations have shown that when radius of (TEA-H) in the linear NCs with n missing air-holes in a line, Ln, reaches to nearly zero value, transition in the structure to the L(n+2) NCs, with roughly different qualities has been observed. Also, improvement in the quality factors of higher-order modes will be achieved. Understanding of the higher-order modes and two dimensional field profiles of the confined photonic modes are useful for the design of more efficient nano-lasers and observation of the cavity QED effects.
The strong localization of electromagnetic modes in high-Q/Vm (quality factor/modal volume) photonic crystal (PhC) nanocavities (NCs) makes them strong candidates for enhanced optical nonlinear effects, such as cavity quantum electrodynamics (QED) phenomena. These applications require precise control of cavity resonances mode. The cavity resonance is strongly depending on the lattice constant, a, and the air-hole radius, r, of photonic crystals. Slight modifications in the geometries of the photonic crystals will result in large differences in the dispersion characteristics. In this paper, by using BandSOLVE and FullWAVE software of RSoft Photonics CAD package, at first L1, L3 and L5 NCs in a semiconductor slab have been simulated in a hexagonal lattice of air-holes (radius r) with lattice constant a=270 nm and constant fill factor (r/a=0.29). Then, with radius reduction of the two ends air-holes (TEA-H), different confinement characteristics of photonic modes such as: numbers of confined modes, wavelengths, quality factors and two dimensional field profiles have been investigated. Calculations have shown that when radius of (TEA-H) in the linear NCs with n missing air-holes in a line, Ln, reaches to nearly zero value, transition in the structure to the L(n+2) NCs, with roughly different qualities has been observed. Also, improvement in the quality factors of higher-order modes will be achieved. Understanding of the higher-order modes and two dimensional field profiles of the confined photonic modes are useful for the design of more efficient nano-lasers and observation of the cavity QED effects.
Air-Holes Radius Change Effects and Structure Transitions in the Linear Photonic Crystal Nanocavities
doi:10.11648/j.ajop.20130103.11
American Journal of Optics and Photonics
2014-01-01
© Science Publishing Group
Ahmadreza Daraei
Foroogh Khozeymeh Sarbisheh
Air-Holes Radius Change Effects and Structure Transitions in the Linear Photonic Crystal Nanocavities
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2014-01-01
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http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20130103.11
© Science Publishing Group
Reducing Measurement Uncertainty of Instruments Based on the Phenomenon of Surface Plasmon Resonance
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Considered in this paper are mechanisms of temperature influence on the results of optical measurements based on the surface Plasmon resonance phenomenon. It has been ascertained that the error of measurement results is related with the temperature influence on the refraction index of substances under study as well as on elements of optical setup in measuring equipment. The authors have experimentally demonstrated the influence of thermal stabilization of measuring equipment on dispersion of results obtained in optical measurements.
Considered in this paper are mechanisms of temperature influence on the results of optical measurements based on the surface Plasmon resonance phenomenon. It has been ascertained that the error of measurement results is related with the temperature influence on the refraction index of substances under study as well as on elements of optical setup in measuring equipment. The authors have experimentally demonstrated the influence of thermal stabilization of measuring equipment on dispersion of results obtained in optical measurements.
Reducing Measurement Uncertainty of Instruments Based on the Phenomenon of Surface Plasmon Resonance
doi:10.11648/j.ajop.20130103.12
American Journal of Optics and Photonics
2014-01-01
© Science Publishing Group
Gleb Dorozinsky
Vladimir Maslov
Anton Samoylov
Yury Ushenin
Reducing Measurement Uncertainty of Instruments Based on the Phenomenon of Surface Plasmon Resonance
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10.11648/j.ajop.20130103.12
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© Science Publishing Group
SHG in IR Region in Mixed Zn1-xMgxSe Crystals
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In the present work the results of investigations of the influence of different parameters on conversion efficiency in mixed Zn1-xMgxSe crystal in conditions of existing experiments are cited. The comparison of the obtained results on conversion efficiency with the analogous experimentally measured values has been made. The results of calculation of the angles of phase matching and angular dispersion coefficients for Zn0.52Mg0.48Se crystal on wavelengths of the IR range are cited. The angular dispersion coefficients for Zn1-xMgxSe have been calculated. The angular width of phase matching has been estimated.
In the present work the results of investigations of the influence of different parameters on conversion efficiency in mixed Zn1-xMgxSe crystal in conditions of existing experiments are cited. The comparison of the obtained results on conversion efficiency with the analogous experimentally measured values has been made. The results of calculation of the angles of phase matching and angular dispersion coefficients for Zn0.52Mg0.48Se crystal on wavelengths of the IR range are cited. The angular dispersion coefficients for Zn1-xMgxSe have been calculated. The angular width of phase matching has been estimated.
SHG in IR Region in Mixed Zn1-xMgxSe Crystals
doi:10.11648/j.ajop.20130104.11
American Journal of Optics and Photonics
2014-01-01
© Science Publishing Group
Rena J. Kasumova
SHG in IR Region in Mixed Zn1-xMgxSe Crystals
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2014-01-01
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© Science Publishing Group
Geometrical Parameters Dependence Towards Ultra-Flat Dispersion Square-Lattice PCF with Selective Liquid Infiltration
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We have performed a numerical analysis of the structural dependence of the PCF parameters towards ultra-flat dispersion in the C-band of communication wavelength. The technique is based on regular square-lattice PCF with all the air-hole of same uniform diameter and the effective size of the air-holes are modified with a selective infiltration of the air-holes with liquids. The dependence of the PCF structural parameters namely air-hole diameter and hole-to-hole distance along with the infiltrating liquid has been investigated in details. It is shown that the infiltrating liquid has critical influence on both the slope and value of dispersion, while pitch only changes the dispersion value whereas air-hole diameter modifies the slope of the dispersion. Our numerical investigation establishes dispersion values as small as 0±0.58ps/(nm-km) over a bandwidth of 622nm in the communication wavelength band (C-band). The proposed design study will be very helpful in high power applications like broadband smooth supercontinuum generation, ASE suppressed amplification etc.
We have performed a numerical analysis of the structural dependence of the PCF parameters towards ultra-flat dispersion in the C-band of communication wavelength. The technique is based on regular square-lattice PCF with all the air-hole of same uniform diameter and the effective size of the air-holes are modified with a selective infiltration of the air-holes with liquids. The dependence of the PCF structural parameters namely air-hole diameter and hole-to-hole distance along with the infiltrating liquid has been investigated in details. It is shown that the infiltrating liquid has critical influence on both the slope and value of dispersion, while pitch only changes the dispersion value whereas air-hole diameter modifies the slope of the dispersion. Our numerical investigation establishes dispersion values as small as 0±0.58ps/(nm-km) over a bandwidth of 622nm in the communication wavelength band (C-band). The proposed design study will be very helpful in high power applications like broadband smooth supercontinuum generation, ASE suppressed amplification etc.
Geometrical Parameters Dependence Towards Ultra-Flat Dispersion Square-Lattice PCF with Selective Liquid Infiltration
doi:10.11648/j.ajop.20130105.11
American Journal of Optics and Photonics
2014-01-01
© Science Publishing Group
Partha Sona Maji
Partha Roy Chaudhuri
Geometrical Parameters Dependence Towards Ultra-Flat Dispersion Square-Lattice PCF with Selective Liquid Infiltration
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© Science Publishing Group
Dispersion Properties of the Square-Lattice Elliptical-Core PCFs
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In this paper the dispersion properties of the elliptical core square-lattice PCF in a silica matrix have been studied. The dispersion curves for the fiber for different hole-to-hole spacing and air-hole diameter has been studies extensively. It has been shown that elliptical-core square lattice PCF with small hole to hole distance () and large-hole diameter (d) can be used for dispersion compensation. A comparison between Elliptical PCF with square and triangular PCF has been performed, taking into account the dispersion properties and the effective area. A final study on the two types of PCFs is carried out when they are single mode in the studied wavelength region.
In this paper the dispersion properties of the elliptical core square-lattice PCF in a silica matrix have been studied. The dispersion curves for the fiber for different hole-to-hole spacing and air-hole diameter has been studies extensively. It has been shown that elliptical-core square lattice PCF with small hole to hole distance () and large-hole diameter (d) can be used for dispersion compensation. A comparison between Elliptical PCF with square and triangular PCF has been performed, taking into account the dispersion properties and the effective area. A final study on the two types of PCFs is carried out when they are single mode in the studied wavelength region.
Dispersion Properties of the Square-Lattice Elliptical-Core PCFs
doi:10.11648/j.ajop.20140201.11
American Journal of Optics and Photonics
2014-01-01
© Science Publishing Group
Partha Sona Maji
Partha Roy Chaudhuri
Dispersion Properties of the Square-Lattice Elliptical-Core PCFs
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© Science Publishing Group
A Theoretical Investigation by DFT Method on CR – 39 Monomer that is a Plastic Polymer Commonly Used in the Manufacture of Eyeglass Lenses
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In this paper, the diallyl (oxybis(ethane-2,1-diyl)) dicarbonate (CR-39 monomer) of molecular structure that is a plastic polymer commonly used in the manufacture of eyeglass lenses, has been examined theoretically. The molecular structure of CR-39 monomer was optimized by Density Functional Theory (DFT) using B3LYP method with STO-3G basis set without specifying any symmetry for the title molecule. The non-linear optical properties were calculated at the same level and the title compound showed a good second order non-linear optical property. Besides, the frontier molecular orbital (HOMO and LUMO) energies and related molecular properties of CR – 39 monomer were investigated by theoretical calculation results.
In this paper, the diallyl (oxybis(ethane-2,1-diyl)) dicarbonate (CR-39 monomer) of molecular structure that is a plastic polymer commonly used in the manufacture of eyeglass lenses, has been examined theoretically. The molecular structure of CR-39 monomer was optimized by Density Functional Theory (DFT) using B3LYP method with STO-3G basis set without specifying any symmetry for the title molecule. The non-linear optical properties were calculated at the same level and the title compound showed a good second order non-linear optical property. Besides, the frontier molecular orbital (HOMO and LUMO) energies and related molecular properties of CR – 39 monomer were investigated by theoretical calculation results.
A Theoretical Investigation by DFT Method on CR – 39 Monomer that is a Plastic Polymer Commonly Used in the Manufacture of Eyeglass Lenses
doi:10.11648/j.ajop.20140201.12
American Journal of Optics and Photonics
2014-01-01
© Science Publishing Group
Fatih Şen
Burhanettin Göker Durdu
Murat Oduncuoğlu
Kürşat Efil
Muharrem Dinçer
A Theoretical Investigation by DFT Method on CR – 39 Monomer that is a Plastic Polymer Commonly Used in the Manufacture of Eyeglass Lenses
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2014-01-01
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http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140201.12
© Science Publishing Group
Study On Noise Reduction of Nozzle Shock Diamond Flow Destroyed by Flexible Components
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It's well known that the high pressure flow running through the nozzle yields shock diamond flow which mainly causes the noise. This work employed flexible components on the nozzle outlet to destroy shock diamond flow and using micro color schlieren technique to visual the dispersion shock diamond. Experiments adjusted conditions of and mesh flexible components for optimal design. The results show that wire diameter 0.5mm of cross flexible component, away from nozzle 0.5cm and 1cm received the noise of 83.8dB, the reducing rate was ca.12.5%. The mesh 100 flexible component away from nozzle 0.5cm received the noise of 75.6dB, the reducing rate was ca. 21.17%.
It's well known that the high pressure flow running through the nozzle yields shock diamond flow which mainly causes the noise. This work employed flexible components on the nozzle outlet to destroy shock diamond flow and using micro color schlieren technique to visual the dispersion shock diamond. Experiments adjusted conditions of and mesh flexible components for optimal design. The results show that wire diameter 0.5mm of cross flexible component, away from nozzle 0.5cm and 1cm received the noise of 83.8dB, the reducing rate was ca.12.5%. The mesh 100 flexible component away from nozzle 0.5cm received the noise of 75.6dB, the reducing rate was ca. 21.17%.
Study On Noise Reduction of Nozzle Shock Diamond Flow Destroyed by Flexible Components
doi:10.11648/j.ajop.20140202.11
American Journal of Optics and Photonics
2014-04-16
© Science Publishing Group
Chung-Hwei Su
Chien-Chih Chen
Yi-Hua Pan
Chen-Ching Ting
Study On Noise Reduction of Nozzle Shock Diamond Flow Destroyed by Flexible Components
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2014-04-16
2014-04-16
10.11648/j.ajop.20140202.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140202.11
© Science Publishing Group
Using Color Full-Scale Schlieren (CFSS) Technique to Improve Kitchen Exhaust Hood Performance
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140202.12
This article uses color full-scale Schlieren for heat flow visualization of the kitchen exhaust hood. Using grease filters with same percentage of opening but different forms for measurements the heat flow escaping rate, noise, and air velocity of the kitchen exhaust hood under conditions of different percentage masking. The results show that using different grease filters without masking has no escaping heat flow. Employing the rectangular filter with side masking has the worst heat flow escaping. The top masking has also no heat flow escaping and the form with circular opening has the strongest absorbability. In this work, the smallest noise level is 65dB which appears at the situation of top masking. Moreover, kitchen exhaust hood without masking the air flow rate increase 3.17% of the air velocity than side masking.
This article uses color full-scale Schlieren for heat flow visualization of the kitchen exhaust hood. Using grease filters with same percentage of opening but different forms for measurements the heat flow escaping rate, noise, and air velocity of the kitchen exhaust hood under conditions of different percentage masking. The results show that using different grease filters without masking has no escaping heat flow. Employing the rectangular filter with side masking has the worst heat flow escaping. The top masking has also no heat flow escaping and the form with circular opening has the strongest absorbability. In this work, the smallest noise level is 65dB which appears at the situation of top masking. Moreover, kitchen exhaust hood without masking the air flow rate increase 3.17% of the air velocity than side masking.
Using Color Full-Scale Schlieren (CFSS) Technique to Improve Kitchen Exhaust Hood Performance
doi:10.11648/j.ajop.20140202.12
American Journal of Optics and Photonics
2014-04-16
© Science Publishing Group
Chung-Hwei Su
Chien-Chih Chen
Li-Yu Yeh
Yu-Cheng Hung
Chen-Ching Ting
Using Color Full-Scale Schlieren (CFSS) Technique to Improve Kitchen Exhaust Hood Performance
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2014-04-16
2014-04-16
10.11648/j.ajop.20140202.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140202.12
© Science Publishing Group
Investigation on the Optical Properties of Nonlinear Optical (NLO) Single Crystal: L-Valine Zinc Hydrochloride
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140203.11
The development and encroachment of high technology, from transportation, computation to information is based on the availability of materials in the form of single crystals. With progress in crystal growth technology and characterization, organic, inorganic, semiorganic and organometallic materials having attractive nonlinear optical (NLO) properties are being discovered at rapid rate. NLO materials possess several attractive properties such as high NLO coefficient, high laser damage threshold, wide transparency range, high mechanical strength and thermal stability, which make the materials suitable for second harmonic generation (SHG) and other NLO applications. Single crystals of L-Valine zinc hydrochloride were grown by the slow evaporation technique. The single crystal X-ray diffraction analysis reveals that the crystal belongs to the monoclinic system. The optical absorption spectrum reveals the transparency of the crystal in the entire visible region and the cut off wave length has been found to be 210 nm. The optical band gap is found to be 5.91 eV. Optical constants such as the band gap (Eg), refractive index (n), reflectance (R), extinction coefficient (K) and the real (εr) and imaginary (εi) components of the dielectric constant and electric susceptibility (c) were determined from the UV-VIS-NIR absorption spectrum.
The development and encroachment of high technology, from transportation, computation to information is based on the availability of materials in the form of single crystals. With progress in crystal growth technology and characterization, organic, inorganic, semiorganic and organometallic materials having attractive nonlinear optical (NLO) properties are being discovered at rapid rate. NLO materials possess several attractive properties such as high NLO coefficient, high laser damage threshold, wide transparency range, high mechanical strength and thermal stability, which make the materials suitable for second harmonic generation (SHG) and other NLO applications. Single crystals of L-Valine zinc hydrochloride were grown by the slow evaporation technique. The single crystal X-ray diffraction analysis reveals that the crystal belongs to the monoclinic system. The optical absorption spectrum reveals the transparency of the crystal in the entire visible region and the cut off wave length has been found to be 210 nm. The optical band gap is found to be 5.91 eV. Optical constants such as the band gap (Eg), refractive index (n), reflectance (R), extinction coefficient (K) and the real (εr) and imaginary (εi) components of the dielectric constant and electric susceptibility (c) were determined from the UV-VIS-NIR absorption spectrum.
Investigation on the Optical Properties of Nonlinear Optical (NLO) Single Crystal: L-Valine Zinc Hydrochloride
doi:10.11648/j.ajop.20140203.11
American Journal of Optics and Photonics
2014-05-27
© Science Publishing Group
Suresh Sagadevan
Investigation on the Optical Properties of Nonlinear Optical (NLO) Single Crystal: L-Valine Zinc Hydrochloride
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2014-05-27
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http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140203.11
© Science Publishing Group
Whispering Gallery Modes Formation in Small Nanocavities Based upon Crossed Nanobeam Structures
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140203.12
In this paper, we investigate conditions to form whispering gallery modes (WGMs) in small nanocavities (NCs) which are designed at the intersection area of couple of nanobeams (NBs) structures. Tapered air-holes at each branch of NBs have been employed as a part of mirror accompanied by curved-walls at cross junctions to form a small curved nanocavity. Simulations by finite element based commercial software, COMSOL Multiphysics 4.3 show that confined photonic modes are well established via WGM mechanism. Variation of modes wavelength and their field intensity profiles have been investigated. Quality factor, Q, as high as 198400 is obtained for a particular WGM at mode wavelength 1471.9 nm with computed modal volume as low as Vmod≈0.25(λ/n)3.
In this paper, we investigate conditions to form whispering gallery modes (WGMs) in small nanocavities (NCs) which are designed at the intersection area of couple of nanobeams (NBs) structures. Tapered air-holes at each branch of NBs have been employed as a part of mirror accompanied by curved-walls at cross junctions to form a small curved nanocavity. Simulations by finite element based commercial software, COMSOL Multiphysics 4.3 show that confined photonic modes are well established via WGM mechanism. Variation of modes wavelength and their field intensity profiles have been investigated. Quality factor, Q, as high as 198400 is obtained for a particular WGM at mode wavelength 1471.9 nm with computed modal volume as low as Vmod≈0.25(λ/n)3.
Whispering Gallery Modes Formation in Small Nanocavities Based upon Crossed Nanobeam Structures
doi:10.11648/j.ajop.20140203.12
American Journal of Optics and Photonics
2014-06-05
© Science Publishing Group
Ahmadreza Daraei
Atefeh Mohsenifard
Mohammad Kafi Meibodi
Whispering Gallery Modes Formation in Small Nanocavities Based upon Crossed Nanobeam Structures
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2014-06-05
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© Science Publishing Group
OLED Display Technology
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140203.13
OLEDs are solid-state devices composed of thin films of organic molecules that create light with the application of electricity. OLEDs can provide brighter, crisper displays on electronic devices and use less power than conventional light-emitting diodes (LEDs) or liquid crystal displays (LCDs) used today. OLEDs are made by placing thin films of organic (carbon based) materials between two conductors. When electrical current is applied, a bright light is emitted. The OLED materials emit light and do not require a backlight (unlike LCDs). Each pixel is a small light-emitting diode, in fact. OLEDs emit light they do not require a backlight and so are thinner and more efficient than LCD displays (which do require a white backlight).In this paper we investigate the characteristics of OLED.
OLEDs are solid-state devices composed of thin films of organic molecules that create light with the application of electricity. OLEDs can provide brighter, crisper displays on electronic devices and use less power than conventional light-emitting diodes (LEDs) or liquid crystal displays (LCDs) used today. OLEDs are made by placing thin films of organic (carbon based) materials between two conductors. When electrical current is applied, a bright light is emitted. The OLED materials emit light and do not require a backlight (unlike LCDs). Each pixel is a small light-emitting diode, in fact. OLEDs emit light they do not require a backlight and so are thinner and more efficient than LCD displays (which do require a white backlight).In this paper we investigate the characteristics of OLED.
OLED Display Technology
doi:10.11648/j.ajop.20140203.13
American Journal of Optics and Photonics
2014-06-26
© Science Publishing Group
Askari Mohammad Bagher
OLED Display Technology
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2014-06-26
10.11648/j.ajop.20140203.13
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140203.13
© Science Publishing Group
Designing a High Speed 1310nm AlGaInAs/AlGaInAs VCSEL using MgO/Si Top DBR and GaInAsP/InP Bottom DBR
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140203.14
In this paper, a 1310nm intracavity structure Vertical Cavity Surface Emitting Laser (VCSEL) has been designed using quaternary compound material of AlGaInAs in both QW and barrier but with different composition. This choice has been made instead of choosing widely used GaInAsP/ InP, GaInAsN/ GaAs to gain some advantages. This combination has shown good band offset in the conduction band. Lattice matching has been obtained in the layers from the substrate up to the top contact layer except the quantum well (QW) layers where small amount of compressive strain of 1.55% has been used. From the substrate up to the top contact layer, fabrication can be done by epitaxial growth without any difficulty. Reduction in height by using 5 pairs of the top dielectric DBR mirror system of MgO/ a-Si is an attraction of this design which can be fabricated by evaporation technique. Dissipation in the bottom DBR due to current flow has been eliminated by using intracavity structure which also gave a way out for the current flow bypassing the dielectric top DBR. The active material compositions have been chosen to obtain a peak gain at 1310nm. The end result of this design is a top emitting VCSEL based on InP substrate using a different structure which is capable of producing 1310nm light output and which can be constructed easily using widely used epitaxial techniques mixed with the evaporation technique for the top DBR mirror system. The structure is suitable for use in optical ICs.
In this paper, a 1310nm intracavity structure Vertical Cavity Surface Emitting Laser (VCSEL) has been designed using quaternary compound material of AlGaInAs in both QW and barrier but with different composition. This choice has been made instead of choosing widely used GaInAsP/ InP, GaInAsN/ GaAs to gain some advantages. This combination has shown good band offset in the conduction band. Lattice matching has been obtained in the layers from the substrate up to the top contact layer except the quantum well (QW) layers where small amount of compressive strain of 1.55% has been used. From the substrate up to the top contact layer, fabrication can be done by epitaxial growth without any difficulty. Reduction in height by using 5 pairs of the top dielectric DBR mirror system of MgO/ a-Si is an attraction of this design which can be fabricated by evaporation technique. Dissipation in the bottom DBR due to current flow has been eliminated by using intracavity structure which also gave a way out for the current flow bypassing the dielectric top DBR. The active material compositions have been chosen to obtain a peak gain at 1310nm. The end result of this design is a top emitting VCSEL based on InP substrate using a different structure which is capable of producing 1310nm light output and which can be constructed easily using widely used epitaxial techniques mixed with the evaporation technique for the top DBR mirror system. The structure is suitable for use in optical ICs.
Designing a High Speed 1310nm AlGaInAs/AlGaInAs VCSEL using MgO/Si Top DBR and GaInAsP/InP Bottom DBR
doi:10.11648/j.ajop.20140203.14
American Journal of Optics and Photonics
2014-07-14
© Science Publishing Group
Arnob Islam
Saiful Islam
Designing a High Speed 1310nm AlGaInAs/AlGaInAs VCSEL using MgO/Si Top DBR and GaInAsP/InP Bottom DBR
2
3
44
44
2014-07-14
2014-07-14
10.11648/j.ajop.20140203.14
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140203.14
© Science Publishing Group
A Research Paper on the Performance Analysis of a Self-Mode Locking High Power Linearly Polarised Fiber Laser
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140204.11
In this research a design for high power linearly polarized all-fiber linear cavity lasers with self-mode-locking is presented, and a new theoretical model based on a Nonlinear Schrödinger Equation (NLSE) is developed and implemented on the MATLAB platform. For the design of cavity, Polarization Maintaining (PM) fibers for both the gain medium and the Fiber Bragg Gratings (FBGs) is implemented. The FBG pairs are used to select the lasing wavelength and polarization. The fiber lasers incorporate specially designed FBGs to achieve an extinction ratio larger than 23 dB. The proposed configuration is based on Non-Linear Polarization (NPR) using PM Yb-doped active fiber and two matching FBGs to form the laser cavity. The combination of nonlinearity, gain, and birefringence in the cavity made the laser generate mode-locked pulses in the picosecond range and with high average output power. Experimental data and numerical simulations of the self-mode-locking fiber laser are presented. Main parameters affecting mode-locked pulses and its envelope are identified. The model proposed here explains the self-mode-locking mechanism and the source of the pulse envelope. In this model, it is proven that self-phase modulation (SPM) plays an essential role in pulse formation and shaping.
In this research a design for high power linearly polarized all-fiber linear cavity lasers with self-mode-locking is presented, and a new theoretical model based on a Nonlinear Schrödinger Equation (NLSE) is developed and implemented on the MATLAB platform. For the design of cavity, Polarization Maintaining (PM) fibers for both the gain medium and the Fiber Bragg Gratings (FBGs) is implemented. The FBG pairs are used to select the lasing wavelength and polarization. The fiber lasers incorporate specially designed FBGs to achieve an extinction ratio larger than 23 dB. The proposed configuration is based on Non-Linear Polarization (NPR) using PM Yb-doped active fiber and two matching FBGs to form the laser cavity. The combination of nonlinearity, gain, and birefringence in the cavity made the laser generate mode-locked pulses in the picosecond range and with high average output power. Experimental data and numerical simulations of the self-mode-locking fiber laser are presented. Main parameters affecting mode-locked pulses and its envelope are identified. The model proposed here explains the self-mode-locking mechanism and the source of the pulse envelope. In this model, it is proven that self-phase modulation (SPM) plays an essential role in pulse formation and shaping.
A Research Paper on the Performance Analysis of a Self-Mode Locking High Power Linearly Polarised Fiber Laser
doi:10.11648/j.ajop.20140204.11
American Journal of Optics and Photonics
2014-10-15
© Science Publishing Group
Bishal Poudel
Om Nath Acharya
A Research Paper on the Performance Analysis of a Self-Mode Locking High Power Linearly Polarised Fiber Laser
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53
53
2014-10-15
2014-10-15
10.11648/j.ajop.20140204.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140204.11
© Science Publishing Group
Influence of Orbital Hybridization on Kerr Nonlinearity of a Heavy Metal Borate Glass: Scaling of Polarizability and the Imaginary Contribution of Optical Susceptibility
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140204.12
Photonics properties of glasses can be designed by controlling their complex Kerr nonlinearity. Chemical structure and bonding properties are considered as the origin of glass third-order susceptibilities. Investigation of the role of orbital hybridization on the glass electronic polarizability and third-order susceptibility is carried out. Thus, series of heavy metal lead borate glass of the composition 0.25B2O3–0.75PbO is prepared by melt quenching technique. Orbital hybridization, as a linear combination for valence electron wave functions of p- and d-block elements, is obtained through structural co-substitution of very small contents of Cr2O3 and/or SeO2, by B2O3. It get succeed to tune the glass nonlinear optical characteristics such as; the complex components of third-order susceptibility. Scaling roles describing the relations between oxide ion polarizability and index of refraction and between imaginary part of third-order susceptibility and band gap energy are proposed. The glasses exhibit zero-dispersion wavelength at 1.55 μm band which is needed for telecommunication devices. The polarizability approach is applied to analyze and explain the obtained glass properties.
Photonics properties of glasses can be designed by controlling their complex Kerr nonlinearity. Chemical structure and bonding properties are considered as the origin of glass third-order susceptibilities. Investigation of the role of orbital hybridization on the glass electronic polarizability and third-order susceptibility is carried out. Thus, series of heavy metal lead borate glass of the composition 0.25B2O3–0.75PbO is prepared by melt quenching technique. Orbital hybridization, as a linear combination for valence electron wave functions of p- and d-block elements, is obtained through structural co-substitution of very small contents of Cr2O3 and/or SeO2, by B2O3. It get succeed to tune the glass nonlinear optical characteristics such as; the complex components of third-order susceptibility. Scaling roles describing the relations between oxide ion polarizability and index of refraction and between imaginary part of third-order susceptibility and band gap energy are proposed. The glasses exhibit zero-dispersion wavelength at 1.55 μm band which is needed for telecommunication devices. The polarizability approach is applied to analyze and explain the obtained glass properties.
Influence of Orbital Hybridization on Kerr Nonlinearity of a Heavy Metal Borate Glass: Scaling of Polarizability and the Imaginary Contribution of Optical Susceptibility
doi:10.11648/j.ajop.20140204.12
American Journal of Optics and Photonics
2014-10-20
© Science Publishing Group
Fouad El-Diasty
Fathy A. Abdel-Wahab
Manal Abdel-Baki
Fouad A. Moustafa
Influence of Orbital Hybridization on Kerr Nonlinearity of a Heavy Metal Borate Glass: Scaling of Polarizability and the Imaginary Contribution of Optical Susceptibility
2
4
64
64
2014-10-20
2014-10-20
10.11648/j.ajop.20140204.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140204.12
© Science Publishing Group
Investigation on Optical Behaviour of Hippuric Acid for Optoelectronics Applications
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140205.11
In present investigation Hippuric Acid (HA) crystal has been grown by slow evaporation technique. The crystalline nature of the grown crystal was confirmed using single X-ray diffraction technique. The optical studies were carried to examine optical transparency and determine the optical constants of the grown crystal quenching the optoelectronics applications. The grown crystal was subjected to optical studies. The optical studies ascertained high optical transparency and cut off wavelength was found to be 300 nm very important for nonlinear applications. The optical band gap of grown crystal is found to be 4.14 eV. The optical constants such as extinction coefficient, refractive index, optical band gap, and reflectance were calculated. The observed etch patterns confirm the layer growth mechanism.
In present investigation Hippuric Acid (HA) crystal has been grown by slow evaporation technique. The crystalline nature of the grown crystal was confirmed using single X-ray diffraction technique. The optical studies were carried to examine optical transparency and determine the optical constants of the grown crystal quenching the optoelectronics applications. The grown crystal was subjected to optical studies. The optical studies ascertained high optical transparency and cut off wavelength was found to be 300 nm very important for nonlinear applications. The optical band gap of grown crystal is found to be 4.14 eV. The optical constants such as extinction coefficient, refractive index, optical band gap, and reflectance were calculated. The observed etch patterns confirm the layer growth mechanism.
Investigation on Optical Behaviour of Hippuric Acid for Optoelectronics Applications
doi:10.11648/j.ajop.20140205.11
American Journal of Optics and Photonics
2014-10-20
© Science Publishing Group
Suresh Sagadevan
Priya Murugasen
Investigation on Optical Behaviour of Hippuric Acid for Optoelectronics Applications
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5
68
68
2014-10-20
2014-10-20
10.11648/j.ajop.20140205.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140205.11
© Science Publishing Group
Electrical and Photoelectrical Properties of Copper (II) Complex/n-Si/Au Heterojunction Diode
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140206.11
In this study, we fabricated copper(II) complex/n-Si/Au organic-inorganic heterojunction diode by forming copper(II) complex thin film on n-type silicon. A direct optical band gap energy values of the copper(II) complex (Cu2C34H34N2O21Cl4) thin film on a glass substrate was obtained as Eg=2.98 eV. The current-voltage (I-V) measurement of the diode was carried out at room temperature and under dark. The ideality factor n and barrier height ϕb values of the diode were found to be 3.17 and 0.71 eV, respectively. The diode indicates non-ideal current-voltage characteristics due to the high ideality factor greater than unity. The series resistance Rs and ideality factor n values were determined using Cheung’s method and obtained as 5.54 kΩ and 3.81, respectively. The capacitance-voltage (C-V) measurements of the diode were performed at different frequency and room temperature. From the analysis of the C-V measurements carrier concentration Nd, diffusion potential Vd and barrier height values ϕbc-v were determined as 2.79x1015 cm-3, 1.078 V, 1.31 eV, respectively. From the I-V measurements of the diode under 1.5 AM illumination, short circuit current (Isc) and open circuit voltage (Voc) have been extracted as 12.8 µA and 153 mV, respectively.
In this study, we fabricated copper(II) complex/n-Si/Au organic-inorganic heterojunction diode by forming copper(II) complex thin film on n-type silicon. A direct optical band gap energy values of the copper(II) complex (Cu2C34H34N2O21Cl4) thin film on a glass substrate was obtained as Eg=2.98 eV. The current-voltage (I-V) measurement of the diode was carried out at room temperature and under dark. The ideality factor n and barrier height ϕb values of the diode were found to be 3.17 and 0.71 eV, respectively. The diode indicates non-ideal current-voltage characteristics due to the high ideality factor greater than unity. The series resistance Rs and ideality factor n values were determined using Cheung’s method and obtained as 5.54 kΩ and 3.81, respectively. The capacitance-voltage (C-V) measurements of the diode were performed at different frequency and room temperature. From the analysis of the C-V measurements carrier concentration Nd, diffusion potential Vd and barrier height values ϕbc-v were determined as 2.79x1015 cm-3, 1.078 V, 1.31 eV, respectively. From the I-V measurements of the diode under 1.5 AM illumination, short circuit current (Isc) and open circuit voltage (Voc) have been extracted as 12.8 µA and 153 mV, respectively.
Electrical and Photoelectrical Properties of Copper (II) Complex/n-Si/Au Heterojunction Diode
doi:10.11648/j.ajop.20140206.11
American Journal of Optics and Photonics
2015-01-15
© Science Publishing Group
Cihat Ozaydin
Kemal Akkilic
Electrical and Photoelectrical Properties of Copper (II) Complex/n-Si/Au Heterojunction Diode
2
6
74
74
2015-01-15
2015-01-15
10.11648/j.ajop.20140206.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20140206.11
© Science Publishing Group
Study of the Electrons Density in the Base of the Parallel Vertical Junction Solar Cell Under the Influence of the Temperature
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150301.13
This work is a theoretical study of a parallel vertical junction solar cell under multispectral illumination in static regime. The expression for the density of the minority carriers in excess (electrons) in the base is determined from the equation of continuity. It's an equation that takes into account the process of generation of the charge carriers, the process of diffusion of these carriers and their processes of recombination process. The aim of this work is to study the evolution of this density depending on temperature and its distribution in depth following x and the thickness z in the base for different values of the temperature.
This work is a theoretical study of a parallel vertical junction solar cell under multispectral illumination in static regime. The expression for the density of the minority carriers in excess (electrons) in the base is determined from the equation of continuity. It's an equation that takes into account the process of generation of the charge carriers, the process of diffusion of these carriers and their processes of recombination process. The aim of this work is to study the evolution of this density depending on temperature and its distribution in depth following x and the thickness z in the base for different values of the temperature.
Study of the Electrons Density in the Base of the Parallel Vertical Junction Solar Cell Under the Influence of the Temperature
doi:10.11648/j.ajop.20150301.13
American Journal of Optics and Photonics
2015-07-29
© Science Publishing Group
Nfally Dieme
Study of the Electrons Density in the Base of the Parallel Vertical Junction Solar Cell Under the Influence of the Temperature
3
1
16
16
2015-07-29
2015-07-29
10.11648/j.ajop.20150301.13
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150301.13
© Science Publishing Group
Population Inversion and X-Ray Laser Gain by Electron Impact Excitation of Ni-Like Tin
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150301.14
Excitation energies and transition probabilities for the 1s22s22p63s23p63d10, and the 1s22s22p63s23p63d94l (l= s, p, d, and f) configurations in nickel-like tin have been used to calculate the reduced population of 99 fine structure levels over a wide range of electron densities and at different electron plasma temperatures. The gain coefficients for those transitions with positive population inversion factors have been calculated as a function of electron density. This study is concerned with the transitions which produce positive gain at XUV and X-ray spectral regions.
Excitation energies and transition probabilities for the 1s22s22p63s23p63d10, and the 1s22s22p63s23p63d94l (l= s, p, d, and f) configurations in nickel-like tin have been used to calculate the reduced population of 99 fine structure levels over a wide range of electron densities and at different electron plasma temperatures. The gain coefficients for those transitions with positive population inversion factors have been calculated as a function of electron density. This study is concerned with the transitions which produce positive gain at XUV and X-ray spectral regions.
Population Inversion and X-Ray Laser Gain by Electron Impact Excitation of Ni-Like Tin
doi:10.11648/j.ajop.20150301.14
American Journal of Optics and Photonics
2015-07-31
© Science Publishing Group
Mahmoud Ahmad
Ahmed Abou El-Maaref
Essam Abdel-Wahab
Sami Allam
Population Inversion and X-Ray Laser Gain by Electron Impact Excitation of Ni-Like Tin
3
1
23
23
2015-07-31
2015-07-31
10.11648/j.ajop.20150301.14
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150301.14
© Science Publishing Group
Parametric Characterization of Truncated Circular Flattened Gaussian Beams
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150301.11
Based on the truncated second-order moments definition, the generalized factor of the circular flattened Gaussian beams (CFGB) in the cylindrical coordinate system through a hard-edged circular aperture is derived. Three special cases have been obtained from the closed-form expression for the generalized factor of the truncated CFGB, the non-truncated CFGB, the truncated and non-truncated Gaussian beams. The power fraction of the CFGB is calculated analytically and illustrated numerically.
Based on the truncated second-order moments definition, the generalized factor of the circular flattened Gaussian beams (CFGB) in the cylindrical coordinate system through a hard-edged circular aperture is derived. Three special cases have been obtained from the closed-form expression for the generalized factor of the truncated CFGB, the non-truncated CFGB, the truncated and non-truncated Gaussian beams. The power fraction of the CFGB is calculated analytically and illustrated numerically.
Parametric Characterization of Truncated Circular Flattened Gaussian Beams
doi:10.11648/j.ajop.20150301.11
American Journal of Optics and Photonics
2015-07-02
© Science Publishing Group
Redouane Lamsoudi
Mohammed Ibn Chaikh
Parametric Characterization of Truncated Circular Flattened Gaussian Beams
3
1
4
4
2015-07-02
2015-07-02
10.11648/j.ajop.20150301.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150301.11
© Science Publishing Group
Performance Analysis of Coherent Optical OFDM Applied to UAV Mobile FSO Systems
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150301.12
The Free Space Optical (FSO) communication links is a promising and cost-effective solution for the provision of high data rate point to point communications. Due to their huge bandwidth, license free spectrum and multipath fading mitigation, the FSO links combined with Orthogonal Frequency Division Multiplexing (OFDM) modulation technique provide an ideal communication solution between Unmanned Aerial Vehicles (UAVs) and fixed Ground Station (GS). In order to design a high performance communication link, it is important to characterize the quality of the optical channel with a proper model, considering the interesting challenges of environmental conditions, such as turbulence and visibility conditions. In this paper we are studying the performance of a mobile link among co-moving UAVs, UAV and GS at different fixed altitudes and link ranges via Optisystem simulation platform, in terms of Bit Error Rate (BER), Optical Signal to Noise Ratio (OSNR) and constellation diagrams. An extensive, comparative analysis among different FSO configurations links considering various characteristics of the OFDM modulation, link ranges, Bit Rates (BR) and the atmospherical conditions is provided.
The Free Space Optical (FSO) communication links is a promising and cost-effective solution for the provision of high data rate point to point communications. Due to their huge bandwidth, license free spectrum and multipath fading mitigation, the FSO links combined with Orthogonal Frequency Division Multiplexing (OFDM) modulation technique provide an ideal communication solution between Unmanned Aerial Vehicles (UAVs) and fixed Ground Station (GS). In order to design a high performance communication link, it is important to characterize the quality of the optical channel with a proper model, considering the interesting challenges of environmental conditions, such as turbulence and visibility conditions. In this paper we are studying the performance of a mobile link among co-moving UAVs, UAV and GS at different fixed altitudes and link ranges via Optisystem simulation platform, in terms of Bit Error Rate (BER), Optical Signal to Noise Ratio (OSNR) and constellation diagrams. An extensive, comparative analysis among different FSO configurations links considering various characteristics of the OFDM modulation, link ranges, Bit Rates (BR) and the atmospherical conditions is provided.
Performance Analysis of Coherent Optical OFDM Applied to UAV Mobile FSO Systems
doi:10.11648/j.ajop.20150301.12
American Journal of Optics and Photonics
2015-07-02
© Science Publishing Group
Konstantinos Eleftherios Zarganis
Antonis Hatziefremidis
Performance Analysis of Coherent Optical OFDM Applied to UAV Mobile FSO Systems
3
1
12
12
2015-07-02
2015-07-02
10.11648/j.ajop.20150301.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150301.12
© Science Publishing Group
Comparison of Different Chromatic Dispersion Compensation Techniques in Radio over Fiber System
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150302.11
In this paper, we investigate the transmission of a 100 Gbit/s signal with 0.1THz carrier frequency using radio over fiber (RoF) for a fiber length of 50km. In our study, the impact of chromatic dispersion on the wireless signals transported through the fiber link and its mitigation using different dispersion compensation techniques are discussed. The techniques discussed here includes the optical single sideband transmission using dual electrode Mach Zehnder modulator, external filtering using FBG and compensation using chirped fiber grating. We also evaluated the performance of the three compensation techniques by plotting the eye diagram. The results clearly depict that compensation using chirped grating is the best among the three methods. The investigation is done on detailed simulative analysis using Optisystem.
In this paper, we investigate the transmission of a 100 Gbit/s signal with 0.1THz carrier frequency using radio over fiber (RoF) for a fiber length of 50km. In our study, the impact of chromatic dispersion on the wireless signals transported through the fiber link and its mitigation using different dispersion compensation techniques are discussed. The techniques discussed here includes the optical single sideband transmission using dual electrode Mach Zehnder modulator, external filtering using FBG and compensation using chirped fiber grating. We also evaluated the performance of the three compensation techniques by plotting the eye diagram. The results clearly depict that compensation using chirped grating is the best among the three methods. The investigation is done on detailed simulative analysis using Optisystem.
Comparison of Different Chromatic Dispersion Compensation Techniques in Radio over Fiber System
doi:10.11648/j.ajop.20150302.11
American Journal of Optics and Photonics
2015-08-11
© Science Publishing Group
Jayasree Vadakke Kadangote
Neethu Johney
Asha Radhamany Somasekharan
Comparison of Different Chromatic Dispersion Compensation Techniques in Radio over Fiber System
3
2
29
29
2015-08-11
2015-08-11
10.11648/j.ajop.20150302.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150302.11
© Science Publishing Group
Reflection and Transmission of Light Beams at a Curved Interface: Coherent State Approach
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150302.12
Phase-space procedure based on coherent state representation is proposed for investigation of reflection and transmission of wave beams at a curved dielectric boundary. Numerical simulations of reflection and transmission of light at various boundaries separating two different dielectrics are carried out. Significant influence of wave-front curvature and polarization of incident beam on the reflectance and transmittance is shown.
Phase-space procedure based on coherent state representation is proposed for investigation of reflection and transmission of wave beams at a curved dielectric boundary. Numerical simulations of reflection and transmission of light at various boundaries separating two different dielectrics are carried out. Significant influence of wave-front curvature and polarization of incident beam on the reflectance and transmittance is shown.
Reflection and Transmission of Light Beams at a Curved Interface: Coherent State Approach
doi:10.11648/j.ajop.20150302.12
American Journal of Optics and Photonics
2015-08-11
© Science Publishing Group
Nikolai I. Petrov
Reflection and Transmission of Light Beams at a Curved Interface: Coherent State Approach
3
2
33
33
2015-08-11
2015-08-11
10.11648/j.ajop.20150302.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150302.12
© Science Publishing Group
Erbium Doped Fiber Lasers for Long Distance Communication Using Network of Fiber Optics
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150303.11
A fiber doped with erbium laser is used in long distance communication over networks of fiber optics. Especially, in under water communication links where optical signals can be amplified by joining erbium-doped fiber at appropriate locations in the network of the fiber. Thus, a signal, when optically transmitted will get amplified and this will be useful when the signal travels between continents. There is no need for converting an optical signal into an electrical signal, amplified and then reintroduced into the fiber for transmission. The latest research trend is to produce ultra-short pulse widths of the order of 100fs and with a pulse repetition rate of the order of 10GHz. Here I have used an Er3+ doped silica fiber for optical pumping λ=0.98µm or λ=1.48µm wavelength using radiation from a diode laser [Fig. 1]. A coupler was used to select the wavelength, which permits this light to reach the optical fiber transmission system, without disturbing the signal. The optical fiber is spliced into the transmission lines, which acts as an optical isolator. This fiber is constantly pumped by the diode laser. When the pulses pass through the system, they get amplified, while the pump light is reduced.
A fiber doped with erbium laser is used in long distance communication over networks of fiber optics. Especially, in under water communication links where optical signals can be amplified by joining erbium-doped fiber at appropriate locations in the network of the fiber. Thus, a signal, when optically transmitted will get amplified and this will be useful when the signal travels between continents. There is no need for converting an optical signal into an electrical signal, amplified and then reintroduced into the fiber for transmission. The latest research trend is to produce ultra-short pulse widths of the order of 100fs and with a pulse repetition rate of the order of 10GHz. Here I have used an Er3+ doped silica fiber for optical pumping λ=0.98µm or λ=1.48µm wavelength using radiation from a diode laser [Fig. 1]. A coupler was used to select the wavelength, which permits this light to reach the optical fiber transmission system, without disturbing the signal. The optical fiber is spliced into the transmission lines, which acts as an optical isolator. This fiber is constantly pumped by the diode laser. When the pulses pass through the system, they get amplified, while the pump light is reduced.
Erbium Doped Fiber Lasers for Long Distance Communication Using Network of Fiber Optics
doi:10.11648/j.ajop.20150303.11
American Journal of Optics and Photonics
2015-08-11
© Science Publishing Group
Thalangunam Krishnaswamy Subramaniam
Erbium Doped Fiber Lasers for Long Distance Communication Using Network of Fiber Optics
3
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37
37
2015-08-11
2015-08-11
10.11648/j.ajop.20150303.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150303.11
© Science Publishing Group
LED Light Spectrum Affects the Photosynthetic Performance of Houttuynia Cordata Seedlings
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150303.12
We investigated the effects of light-emitting diodes (LED) with various light spectrum (white, red, yellow, green and blue) on photosynthesis of Houttuynia cordata seedlings. The seedlings were either cultivated under florescent lamp or under various LED lights. The leaves were collected and chlorophyll fluorescence parameters, the contents of chlorophyll, soluble sugar and relative water were measured, chloroplasts were observed as well. The results showed chlorophyll fluorescence parameters as Fv/Fm, qP and qY values were the highest under blue LED light and the values were the lowest under green LED light. Red LED light resulted in the enhanced chlorophyll content compared with the other LED lights, and the chl a/chl b ratio did not change significantly among LED treatments. The soluble sugar content was not significantly different among the treatments. The red LED increased relative water content and the green LED decreased the water content. Observation of chloroplasts in the leaves of Houttuynia cordata seedlings showed chloroplast number and distribution were altered by various light spectrum where chloroplasts were smaller under blue LED, and appeared to be more scattered under red LED. Our results indicated that photosynthesis of Houttuynia cordata seedlings respond differently to various light spectrum emitted by florescent lamp and LED
We investigated the effects of light-emitting diodes (LED) with various light spectrum (white, red, yellow, green and blue) on photosynthesis of Houttuynia cordata seedlings. The seedlings were either cultivated under florescent lamp or under various LED lights. The leaves were collected and chlorophyll fluorescence parameters, the contents of chlorophyll, soluble sugar and relative water were measured, chloroplasts were observed as well. The results showed chlorophyll fluorescence parameters as Fv/Fm, qP and qY values were the highest under blue LED light and the values were the lowest under green LED light. Red LED light resulted in the enhanced chlorophyll content compared with the other LED lights, and the chl a/chl b ratio did not change significantly among LED treatments. The soluble sugar content was not significantly different among the treatments. The red LED increased relative water content and the green LED decreased the water content. Observation of chloroplasts in the leaves of Houttuynia cordata seedlings showed chloroplast number and distribution were altered by various light spectrum where chloroplasts were smaller under blue LED, and appeared to be more scattered under red LED. Our results indicated that photosynthesis of Houttuynia cordata seedlings respond differently to various light spectrum emitted by florescent lamp and LED
LED Light Spectrum Affects the Photosynthetic Performance of Houttuynia Cordata Seedlings
doi:10.11648/j.ajop.20150303.12
American Journal of Optics and Photonics
2015-08-11
© Science Publishing Group
Zhaoqing Wang
Jingyun Tian
Bo Yu
Liyan Yang
Yi Sun
LED Light Spectrum Affects the Photosynthetic Performance of Houttuynia Cordata Seedlings
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3
42
42
2015-08-11
2015-08-11
10.11648/j.ajop.20150303.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150303.12
© Science Publishing Group
A Study of Beam Parameters Using NLSE in Chalcogenide Glass Through Variational Method with a Gaussian Trial Function
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150304.11
Using variational method for an elliptical Gaussian optical beam trial function, self –action in bulk chalcogenide glass (Kerr media) is investigated. Emphasis is laid on the study of variation in beam width, curvature, phase and intensity of the beam with propagation distance. Solutions predict stationary self-focusing of the elliptical beam and an effective beam collapse at 10Pcr input power. These study is significant in the choice of parameters in optical communications
Using variational method for an elliptical Gaussian optical beam trial function, self –action in bulk chalcogenide glass (Kerr media) is investigated. Emphasis is laid on the study of variation in beam width, curvature, phase and intensity of the beam with propagation distance. Solutions predict stationary self-focusing of the elliptical beam and an effective beam collapse at 10Pcr input power. These study is significant in the choice of parameters in optical communications
A Study of Beam Parameters Using NLSE in Chalcogenide Glass Through Variational Method with a Gaussian Trial Function
doi:10.11648/j.ajop.20150304.11
American Journal of Optics and Photonics
2015-08-11
© Science Publishing Group
Chironjit Hazarika
Abhijeet Das
Subrata Hazarika
A Study of Beam Parameters Using NLSE in Chalcogenide Glass Through Variational Method with a Gaussian Trial Function
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47
47
2015-08-11
2015-08-11
10.11648/j.ajop.20150304.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150304.11
© Science Publishing Group
The Ellipsometrical Analysis of External Reflection of Light on Superficial Films on Solid Substrates
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150304.12
The ellipsometrical analysis of the external specular reflection of light on nonabsorbing superficial films allows us to know factors which influence the ellipsometric measurement of the analyzed system. For optical nonabsorbing superficial films the curves =f(d<sub>f</sub>) and =f(d<sub>f</sub>) are periodical, while the curves =f() are closed. The paper presents observations on the dependence of the ellipsometric parameters and on d<sub>f</sub>. The analysis of the periodicity of these curves allows us to correctly determine the film thickness for thicknesses greater than d<sub>min</sub>. The value of d<sub>min</sub> depends on the refractive index n<sub>f</sub> of the surface film, the incidence angle φ0 and the wavelength λ of the incident radiation. The dependence of d<sub>min</sub> on n<sub>f</sub>, φ0 and λ is analyzed. From the curve shape we can draw conclusions with respect to the domain of small errors, allowing us to correctly determine the thickness and refraction index of superficial films.
The ellipsometrical analysis of the external specular reflection of light on nonabsorbing superficial films allows us to know factors which influence the ellipsometric measurement of the analyzed system. For optical nonabsorbing superficial films the curves =f(d<sub>f</sub>) and =f(d<sub>f</sub>) are periodical, while the curves =f() are closed. The paper presents observations on the dependence of the ellipsometric parameters and on d<sub>f</sub>. The analysis of the periodicity of these curves allows us to correctly determine the film thickness for thicknesses greater than d<sub>min</sub>. The value of d<sub>min</sub> depends on the refractive index n<sub>f</sub> of the surface film, the incidence angle φ0 and the wavelength λ of the incident radiation. The dependence of d<sub>min</sub> on n<sub>f</sub>, φ0 and λ is analyzed. From the curve shape we can draw conclusions with respect to the domain of small errors, allowing us to correctly determine the thickness and refraction index of superficial films.
The Ellipsometrical Analysis of External Reflection of Light on Superficial Films on Solid Substrates
doi:10.11648/j.ajop.20150304.12
American Journal of Optics and Photonics
2015-08-11
© Science Publishing Group
Simion Jitian
The Ellipsometrical Analysis of External Reflection of Light on Superficial Films on Solid Substrates
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53
53
2015-08-11
2015-08-11
10.11648/j.ajop.20150304.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150304.12
© Science Publishing Group
Possible Existence of Superluminal Photons Inside Microtubules and the Resulting Explanation for Brain Mechanism
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150305.11
D.Georgiev presented an idea that consciousness could be the result of quantum computation via short laser-like pulses controlling quantum gates within the brain cortex. However, he later rejected this theory because the wavelength of super radiant photon emission in the infrared spectrum is two orders of magnitude longer than the size of any microtubule cavity. To revive this idea of quantum computation within the brain, the authors propose that the substance within a microtubule cylinder has the characteristics of a metamaterial composed of sub-wavelength structures. Using this hypothesis, we can propose the mechanism for human brain based on superluminal photons
D.Georgiev presented an idea that consciousness could be the result of quantum computation via short laser-like pulses controlling quantum gates within the brain cortex. However, he later rejected this theory because the wavelength of super radiant photon emission in the infrared spectrum is two orders of magnitude longer than the size of any microtubule cavity. To revive this idea of quantum computation within the brain, the authors propose that the substance within a microtubule cylinder has the characteristics of a metamaterial composed of sub-wavelength structures. Using this hypothesis, we can propose the mechanism for human brain based on superluminal photons
Possible Existence of Superluminal Photons Inside Microtubules and the Resulting Explanation for Brain Mechanism
doi:10.11648/j.ajop.20150305.11
American Journal of Optics and Photonics
2015-08-11
© Science Publishing Group
Takaaki Musha
Luigi Maxmilian Caligiuri
Possible Existence of Superluminal Photons Inside Microtubules and the Resulting Explanation for Brain Mechanism
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57
57
2015-08-11
2015-08-11
10.11648/j.ajop.20150305.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150305.11
© Science Publishing Group
Stimulated Thermal Scattering Induced by Two-Photon Absorption and Experimental Observation of the Genuine Stimulated Brillouin Scattering in the Near-Ultraviolet Region
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150305.13
Part of the experimental measurements of the frequency shift and the phase-conjugation (PC) fidelity gained from previous studies of stimulated scattering (SS) of nanosecond ( ) near-ultraviolet (UV) ( ) laser pulses in liquids (hexane, heptane, and others) are found to disagree with the theory of SS, which takes into account only the linear (single-photon) light absorption. To resolve the inconsistency, SS of XeCl excimer laser radiation ( ) with the duration of in liquid hexane is investigated experimentally. A theoretical analysis of the results obtained revealed three new nonlinear optical phenomena induced by the heating due to two-photon absorption: stimulated thermal scattering (two-photon STS-2), phase mismatch for stimulated Brillouin scattering (SBS), and phase self-modulation. Experimental SS spectrum contains two new lines - a previously unknown two-photon STS-2 line and a genuine SBS line newly discovered in the near-UV region
Part of the experimental measurements of the frequency shift and the phase-conjugation (PC) fidelity gained from previous studies of stimulated scattering (SS) of nanosecond ( ) near-ultraviolet (UV) ( ) laser pulses in liquids (hexane, heptane, and others) are found to disagree with the theory of SS, which takes into account only the linear (single-photon) light absorption. To resolve the inconsistency, SS of XeCl excimer laser radiation ( ) with the duration of in liquid hexane is investigated experimentally. A theoretical analysis of the results obtained revealed three new nonlinear optical phenomena induced by the heating due to two-photon absorption: stimulated thermal scattering (two-photon STS-2), phase mismatch for stimulated Brillouin scattering (SBS), and phase self-modulation. Experimental SS spectrum contains two new lines - a previously unknown two-photon STS-2 line and a genuine SBS line newly discovered in the near-UV region
Stimulated Thermal Scattering Induced by Two-Photon Absorption and Experimental Observation of the Genuine Stimulated Brillouin Scattering in the Near-Ultraviolet Region
doi:10.11648/j.ajop.20150305.13
American Journal of Optics and Photonics
2015-08-13
© Science Publishing Group
Vladimir Boris Karpov
Stimulated Thermal Scattering Induced by Two-Photon Absorption and Experimental Observation of the Genuine Stimulated Brillouin Scattering in the Near-Ultraviolet Region
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79
79
2015-08-13
2015-08-13
10.11648/j.ajop.20150305.13
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150305.13
© Science Publishing Group
Numerical Analysis of Dry Excavation Using a Tie Back Wall Under Static and Dynamic Load
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150305.12
Deep excavations are common in urban areas, nearby existing constructions. The support systems have the main function of preserve the stability and control soil displacements close to the excavation. Settlement control of nearby structures is an essential aspect during design and construction. Settlements prediction is usually made by empirical methods and in some cases also by numerical modeling. The paper presents a numerical modeling of a dry excavation by Plaxis program. The program allows the prediction of stress and deformation behavior of different geotechnical constructions using the Finite Element Method. The excavation has been modeled in five stages, in order to reproduce the construction phases. The numerical modeling was capable to reproduce satisfactorily the horizontal profile of the displacements of the diaphragm wall. In relation to settlements, the shape of the settlement profile was quite similar
Deep excavations are common in urban areas, nearby existing constructions. The support systems have the main function of preserve the stability and control soil displacements close to the excavation. Settlement control of nearby structures is an essential aspect during design and construction. Settlements prediction is usually made by empirical methods and in some cases also by numerical modeling. The paper presents a numerical modeling of a dry excavation by Plaxis program. The program allows the prediction of stress and deformation behavior of different geotechnical constructions using the Finite Element Method. The excavation has been modeled in five stages, in order to reproduce the construction phases. The numerical modeling was capable to reproduce satisfactorily the horizontal profile of the displacements of the diaphragm wall. In relation to settlements, the shape of the settlement profile was quite similar
Numerical Analysis of Dry Excavation Using a Tie Back Wall Under Static and Dynamic Load
doi:10.11648/j.ajop.20150305.12
American Journal of Optics and Photonics
2015-08-13
© Science Publishing Group
Masih Allahbakhshi
Amir Allahbakhshi
Numerical Analysis of Dry Excavation Using a Tie Back Wall Under Static and Dynamic Load
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64
64
2015-08-13
2015-08-13
10.11648/j.ajop.20150305.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150305.12
© Science Publishing Group
Electron-Hole and Photon Recombination Processes in Quantum Well Semiconductor Lasers
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150305.14
The success obtained from semiconductor laser devices is dependent on the science of manipulating the electron-hole and the photon. While the most useful interaction in the laser is the recombination process that involves the electron and holes to produce a photon, other non-useful processes also occur and in some cases overshadow the preferred recombination process. In this review article, the physics behind radiative and non-radiative recombination processes and loss mechanisms dominant in quantum well semiconductor lasers is presented. The work concludes by suggesting possible solutions based on relevant published works
The success obtained from semiconductor laser devices is dependent on the science of manipulating the electron-hole and the photon. While the most useful interaction in the laser is the recombination process that involves the electron and holes to produce a photon, other non-useful processes also occur and in some cases overshadow the preferred recombination process. In this review article, the physics behind radiative and non-radiative recombination processes and loss mechanisms dominant in quantum well semiconductor lasers is presented. The work concludes by suggesting possible solutions based on relevant published works
Electron-Hole and Photon Recombination Processes in Quantum Well Semiconductor Lasers
doi:10.11648/j.ajop.20150305.14
American Journal of Optics and Photonics
2015-08-19
© Science Publishing Group
Barnbas Achakpa Ikyo
Electron-Hole and Photon Recombination Processes in Quantum Well Semiconductor Lasers
3
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84
84
2015-08-19
2015-08-19
10.11648/j.ajop.20150305.14
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150305.14
© Science Publishing Group
Catalytic Synthesis of Hydroquinone by Using Rh on Al2O3 Via Different Rout
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150305.15
The catalytic synthesis of hydroquinoneutilize benzene as the starting material. The manufacture of hydroquinone by oxidation of phenol and 1,2- diisopropylbenzene. The first route begin with Friedel-Crafts alkylation of petroleum –derived benzene to afford cumene. Subsequent Hock-type, air oxidation of the cumene leads to formation of acetone and phenol. The phenol is oxidized by using 70%hydrogen peroxide either in the presence of transition metal or in formic acid solution where formic acid is the actual oxidant. The generated catechol and hydroquinone mixture is separated into its pure components by distillations. The second synthesis way, which is also manufactured, is the reaction with propene and benzene to1,4-diisopropylbenzene, which reacts afterwards to the hydroquinone. Nevertheless there are more than this two synthetic routes benzene reacts to nitrobenzene by using HNO3and H2SO4 and after that to the corresponding aniline. Next, benzoquinone is synthesized by a route employing stoichiometric amounts of MnO2 to oxidize aniline, followed by iron catalyzed reduction to the corresponding hydroquinone. While benzene is a volatile carcinogen derived from non-renewable fossil fuel feed stocks, an alternative way to hydroquinone has been elaborated. Glucose is nonvolatile, nontoxic, and derived from renewable plant polysacharrides and plays an important role for these benzene free 3-dehydroshikimic acid (DHS). Shikimicacid as well as quinic acid are known for the hydroquinone Synthesis. In this work the starting material for the hydroquinone synthesis using catalyzed by Rh/Al2O3,Rh/C, Pt/C, or Pd/c. The Rh on Al2O3 catalyst showed the best results (59% yield)
The catalytic synthesis of hydroquinoneutilize benzene as the starting material. The manufacture of hydroquinone by oxidation of phenol and 1,2- diisopropylbenzene. The first route begin with Friedel-Crafts alkylation of petroleum –derived benzene to afford cumene. Subsequent Hock-type, air oxidation of the cumene leads to formation of acetone and phenol. The phenol is oxidized by using 70%hydrogen peroxide either in the presence of transition metal or in formic acid solution where formic acid is the actual oxidant. The generated catechol and hydroquinone mixture is separated into its pure components by distillations. The second synthesis way, which is also manufactured, is the reaction with propene and benzene to1,4-diisopropylbenzene, which reacts afterwards to the hydroquinone. Nevertheless there are more than this two synthetic routes benzene reacts to nitrobenzene by using HNO3and H2SO4 and after that to the corresponding aniline. Next, benzoquinone is synthesized by a route employing stoichiometric amounts of MnO2 to oxidize aniline, followed by iron catalyzed reduction to the corresponding hydroquinone. While benzene is a volatile carcinogen derived from non-renewable fossil fuel feed stocks, an alternative way to hydroquinone has been elaborated. Glucose is nonvolatile, nontoxic, and derived from renewable plant polysacharrides and plays an important role for these benzene free 3-dehydroshikimic acid (DHS). Shikimicacid as well as quinic acid are known for the hydroquinone Synthesis. In this work the starting material for the hydroquinone synthesis using catalyzed by Rh/Al2O3,Rh/C, Pt/C, or Pd/c. The Rh on Al2O3 catalyst showed the best results (59% yield)
Catalytic Synthesis of Hydroquinone by Using Rh on Al2O3 Via Different Rout
doi:10.11648/j.ajop.20150305.15
American Journal of Optics and Photonics
2015-08-20
© Science Publishing Group
Ved Prakash Singh
Sumit Kumar Pandey
Catalytic Synthesis of Hydroquinone by Using Rh on Al2O3 Via Different Rout
3
5
88
88
2015-08-20
2015-08-20
10.11648/j.ajop.20150305.15
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150305.15
© Science Publishing Group
Quanto-Optical Effects of Exciton-Polariton System
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150305.16
The mutual quantum and optical effects of exciton bound states in exciton-polartiton system in the inhomogeneous multi-layer environment in semiconductor quantum dots (SQDs) are presented. We theoretically show that how optical effects (polarization) of exciton-polariton system can affect on quantum characteristics (spin projections) which results in beats between right- and left-circularly polarized photoluminescence. Optical polarization effects in exciton-polariton interactions in SQDs enable complete studies of the exciton-polariton spin dynamics. The theoretical information on the exotic-polariton states and definition of Hamiltonian interactions according to the basis investigation of the asymptotically bihaviour of the loop function of scalar particles (electron-hole) in SQDs are determined. Using oscillator representation method, spin Hamiltonian coefficient of excitons with effective confinement potential, Coulomb and spin effects are determined. In addition we can say that controlling and understanding of spin interaction between electron- holes localized in SQDs can controlled optically effects and interactions. Spin quantum manipulations can be useful in new generation of optic-photonic studies, especially super quantum computers, Bose condensates of exciton-polariton, polariton lasers and etc
The mutual quantum and optical effects of exciton bound states in exciton-polartiton system in the inhomogeneous multi-layer environment in semiconductor quantum dots (SQDs) are presented. We theoretically show that how optical effects (polarization) of exciton-polariton system can affect on quantum characteristics (spin projections) which results in beats between right- and left-circularly polarized photoluminescence. Optical polarization effects in exciton-polariton interactions in SQDs enable complete studies of the exciton-polariton spin dynamics. The theoretical information on the exotic-polariton states and definition of Hamiltonian interactions according to the basis investigation of the asymptotically bihaviour of the loop function of scalar particles (electron-hole) in SQDs are determined. Using oscillator representation method, spin Hamiltonian coefficient of excitons with effective confinement potential, Coulomb and spin effects are determined. In addition we can say that controlling and understanding of spin interaction between electron- holes localized in SQDs can controlled optically effects and interactions. Spin quantum manipulations can be useful in new generation of optic-photonic studies, especially super quantum computers, Bose condensates of exciton-polariton, polariton lasers and etc
Quanto-Optical Effects of Exciton-Polariton System
doi:10.11648/j.ajop.20150305.16
American Journal of Optics and Photonics
2015-08-20
© Science Publishing Group
Arezu Jahanshir
Quanto-Optical Effects of Exciton-Polariton System
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93
93
2015-08-20
2015-08-20
10.11648/j.ajop.20150305.16
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150305.16
© Science Publishing Group
Types of Solar Cells and Application
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150305.17
A solar cell is an electronic device which directly converts sunlight into electricity. Light shining on the solar cell produces both a current and a voltage to generate electric power. This process requires firstly, a material in which the absorption of light raises an electron to a higher energy state, and secondly, the movement of this higher energy electron from the solar cell into an external circuit. The electron then dissipates its energy in the external circuit and returns to the solar cell. A variety of materials and processes can potentially satisfy the requirements for photovoltaic energy conversion, but in practice nearly all photovoltaic energy conversion uses semiconductor materials in the form of a p-n junction. With regard to the development of sustainable energy, such as solar energy, in this article we will Study types of solar cells and their applications
A solar cell is an electronic device which directly converts sunlight into electricity. Light shining on the solar cell produces both a current and a voltage to generate electric power. This process requires firstly, a material in which the absorption of light raises an electron to a higher energy state, and secondly, the movement of this higher energy electron from the solar cell into an external circuit. The electron then dissipates its energy in the external circuit and returns to the solar cell. A variety of materials and processes can potentially satisfy the requirements for photovoltaic energy conversion, but in practice nearly all photovoltaic energy conversion uses semiconductor materials in the form of a p-n junction. With regard to the development of sustainable energy, such as solar energy, in this article we will Study types of solar cells and their applications
Types of Solar Cells and Application
doi:10.11648/j.ajop.20150305.17
American Journal of Optics and Photonics
2015-08-22
© Science Publishing Group
Askari Mohammad Bagher
Mirzaei Mahmoud Abadi Vahid
Mirhabibi Mohsen
Types of Solar Cells and Application
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113
113
2015-08-22
2015-08-22
10.11648/j.ajop.20150305.17
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150305.17
© Science Publishing Group
Analysis of Near System in Terms of Image Retrieval
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150305.18
In this paper, Near Set Evaluation and Recognition (NEAR) system has been evaluated and analyzed to retrieve perceptual information among images which can resemble human perception. NEAR System is a basic tool for image processing. Different image databases with varied category have been examined to determine the similarity among them. Work is preceded by partitioning an image into different objects. Nearness is performed on the basis of these objects. Work is done in version V3.0 of NEAR System. Calculation of equivalence classes, tolerance classes, segmentation evaluation, nearness among different images has been analyzed
In this paper, Near Set Evaluation and Recognition (NEAR) system has been evaluated and analyzed to retrieve perceptual information among images which can resemble human perception. NEAR System is a basic tool for image processing. Different image databases with varied category have been examined to determine the similarity among them. Work is preceded by partitioning an image into different objects. Nearness is performed on the basis of these objects. Work is done in version V3.0 of NEAR System. Calculation of equivalence classes, tolerance classes, segmentation evaluation, nearness among different images has been analyzed
Analysis of Near System in Terms of Image Retrieval
doi:10.11648/j.ajop.20150305.18
American Journal of Optics and Photonics
2015-08-25
© Science Publishing Group
Sumit Kumar Pandey
Kunal Kumar
Analysis of Near System in Terms of Image Retrieval
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117
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2015-08-25
2015-08-25
10.11648/j.ajop.20150305.18
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150305.18
© Science Publishing Group
Simultaneous <i>in situ</i> Detection of the Optical Fluorescence, Fluorescence Recovery Kinetics After Photobleaching & Membrane Ion Flux on the Electrophysiological Lab-on-a-Chip
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150305.19
The need for simultaneous data recording from multiple channels and synchronization of the correlation data processing in patch-clamp on microelectrode arrays / chips with many data capture points corresponding to single channel ionic kinetic processes of individual cells leads to the idea that adaptive variation of the local potential registration conditions in multichannel devices without signal preprocessing in real time is impossible. Moreover, the advisability of direct registration coupling with the model realization for kinetic identification of the process during patch-clamp can be realized only in case of their synchronization. We propose here such a measurement system.
The need for simultaneous data recording from multiple channels and synchronization of the correlation data processing in patch-clamp on microelectrode arrays / chips with many data capture points corresponding to single channel ionic kinetic processes of individual cells leads to the idea that adaptive variation of the local potential registration conditions in multichannel devices without signal preprocessing in real time is impossible. Moreover, the advisability of direct registration coupling with the model realization for kinetic identification of the process during patch-clamp can be realized only in case of their synchronization. We propose here such a measurement system.
Simultaneous <i>in situ</i> Detection of the Optical Fluorescence, Fluorescence Recovery Kinetics After Photobleaching & Membrane Ion Flux on the Electrophysiological Lab-on-a-Chip
doi:10.11648/j.ajop.20150305.19
American Journal of Optics and Photonics
2015-09-07
© Science Publishing Group
Paul Alexandrov
Alexander Notchenko
Margaret Gradova
Oleg Gradov
Simultaneous <i>in situ</i> Detection of the Optical Fluorescence, Fluorescence Recovery Kinetics After Photobleaching & Membrane Ion Flux on the Electrophysiological Lab-on-a-Chip
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122
122
2015-09-07
2015-09-07
10.11648/j.ajop.20150305.19
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=127&doi=10.11648/j.ajop.20150305.19
© Science Publishing Group