Preferred Language
Articles
/
ijl-340
PDF Design Optical BPF Using Double Clad Fiber MZI for Free Space Optical Communication: Mohanad G. Khamees , Tahreer S. Mansour*
...Show More Authors

Abstract: A novel design of Mach Zehnder Interferometer (MZI) in terms of using special type of optical fiber that has double clad with graded distribution of the refractive index that can be easily implemented practically was suggested and simulated in this work. The suggested design is compact, rapid, and is simple to be modified and tested. The simulated design contains a MZI of 1546.74 nm of central wavelength that is constructed using special type of double clad optical fiber that has two different numerical apertures. The first aperture will supply single mode propagation via its core, while the second numerical aperture supports a zigzag wave propagation (multimode) in the first clad region. The interferometer’s sensing arm (double clad fiber) was etched using 40% Hydro-Fluoric (HF) acid to achieve three different fiber diameters, which are ( 84, 72, 54 ) µm with ( 5 ) cm length. The simulation programs Optiwave version 15 and Optigrating version 4.2.2 were used to simulate the setup and to acquire the readings for the three durations of etching (10, 20, and 30) min, and also for the case of no etching at all. The obtained results show that the simulated setup can be used efficiently to test which one of the etching cases has the highest effect on the performance of the overall system, specifically when it comes to spectrum bandwidth, signal amplitude, and received power.

 

The simulated design contains a MZI of 1546.74 n. meter of central reflection wavelength that is constructed from different types of optical fibers. The used Double Clad (DC) optical fiber diameter was reduced in 3 steps as if it was etched using Hydro-Fluoric (HF) acid to achieve three additional different diameters, which are (84, 72, 54) µ. meters in addition to the default 125 µ. meters.

 

The simulation programs (Optiwave and Optigrating) were used to simulate the setup and to acquire the readings for the three durations of etching (10, 20, and 30) min, and also for the case of no etching at all. The obtained results show that the simulated setup can be used efficiently to test which one of the etching cases has the highest effect on the performance of the overall system, specifically when it comes to spectrum bandwidth, signal amplitude, and received power.

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Sat Jan 05 2019
Journal Name
Iraqi Journal Of Physics
Annealing effect on the optical properties of organic semiconductor Alq3: C60 blend thin films
...Show More Authors

The effect of heat treatment using different annealing temperatures on optical properties of bulk heterojunction blend (BHJ) Alq3: C60 thin films which are fabricated by the spin coating technique were investigated in this study. The films have been coated on a glass substrate with speed of 2000 rpm for one min and treated with different annealing temperature (373, 423 and 473) K under vacuum. The optical properties and the chemical bonds structure of blends as-deposited and heat treated have been studied by UV-Vis spectroscopic and Fourier Transform-Infra Red (FTIR) measurements respectively. The results of UV visible show that the optical energy gap decreasing with increasing the annealing temperature for the ratio (100:1) while decrea

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun May 26 2019
Journal Name
Iraqi Journal Of Science
Substrate Temperature Influence on Optical Properties of C60 Thin Films Within the Visible Range
...Show More Authors

Fullerene thin films of about 200 nm thicknesses have been deposited by thermal evaporation method on soda lime glass at substrate temperature 303 and 403K under pressure about 10-5 mbar. This study concentrated on the influence of substrate temperature on the optical properties of C60 thin films within the visible range. Optical characterization has been carried out at room temperature using the absorption spectra, at normal incidence, in range (200-900) nm.

The absorption and extinction coefficients of the samples have been evaluated according to the variation in the UV- Visible spectrum. Increasing substrate temperature causes decreasing in optical band gap energy, for direct allowed tran

... Show More
View Publication Preview PDF
Crossref (1)
Scopus Crossref
Publication Date
Mon Oct 01 2012
Journal Name
Iraqi Journal Of Physics
Effect of Cu doping on optical properties of Mn2O3 films prepared by spray pyrolysis
...Show More Authors

Thin films of Mn2O3 doped with Cu have been fabricated using the simplest and cheapest chemical spray pyrolysis technique onto a glass substrate heated up to 250 oC. Transmittance and absorptance spectra were studied in the wavelength range (300 -1100) nm. The average transmittance at low energy was about 60% and decrease with Cu doping, Optical constants like refractive index, extinction coefficient and dielectric constants (εr), (εi) are calculated and correlated with doping process.

View Publication Preview PDF
Publication Date
Sun Apr 29 2018
Journal Name
Iraqi Journal Of Science
A Study of Heating Effect on the Structural and Optical Absorbance of Olive Oil
...Show More Authors

     In this study, the number of times of heating of olive oil was studied. For the different refineries, the study was conducted using a temperature of 300K and for several times to determine the validity of the olive oil which is used for frying purposes after it was used for more than once times. It was found that there were significant changes in the behavior of the photophysical behavior like absorption and emission; there are changes in the nature and composition of the olive oil molecule, which makes it not useful for human use. The number of heating times was ten. The heating times also showed significant changes in the nature of the oil, such as color, taste, density, and smell.

View Publication Preview PDF
Publication Date
Thu Mar 09 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Effect of Gamma Ray Irradiation on Structural and Optical Properties of ZnO Thin Films
...Show More Authors

In this research, the structural and optical measurements were made on the Zinc oxide (ZnO) films prepared by two methods once by using chemical spray pyrolysis technique, and another by using thermal evaporation technique before and after irradiation by Gamma –Ray (γ – rays) from source type (Cs 137) with an energy (0.611)MeV as a function of gamma dose (0.15,0.3 and 0.45) Gy. The thickness of all films prepared by two method was about (300 ± 50) nm. XRD is used to characterize the structural properties, the results demonstrated that all samples prepared by two method before and after irradiation have polycrystalline structure with a preferred orientation (002).Also it showed that the structural properties are weakly

... Show More
View Publication Preview PDF
Publication Date
Mon Feb 18 2019
Journal Name
Iraqi Journal Of Physics
Study of optical properties of (PMMA) doped by methyl red and methyl blue films
...Show More Authors

The effect of doping by methyl red and methyl blue on the absorption spectra and the optical energy gap of poly (methyl methacrylat) PMMA film have been studied. The optical transmission (T%) in the wavelength range 190-900 nm for films deposited by using solvent casting method were measured. The Absorptance data reveals that the doping affected the absorption edge as a red and blue shift in its values. The films show indirect allowed interband transitions that influenced by the doping. Optical constants; refractive index, extinction coefficient and real and imaginary part of dielectric constant were calculated and correlated with doping.

View Publication Preview PDF
Crossref
Publication Date
Mon Apr 10 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Effect of Doping Cu on the Structural and Optical Properties of (CdTe) Thin Films
...Show More Authors

   In this research we studied  the structural and optical properties of (CdTe) thin films which have been prepared  by thermal evaporation deposition method on the glass substrate at R.T with thickness (450  25) nm., as  a function of doping  ratio with copper element  in (1,3,5) % rate .The structure  measurement  by X-ray diffraction (XRD) analyses shows that the single phase of (CdTe) with polycrystalline structure with a preferred orientation [111].   The optical  measurement shows that the (CdTe) films have a direct energy gap, and they decrease with the increase of doping ratio reaching to 5% . The optical constants are investigated and calculated, such as absorpti

... Show More
View Publication Preview PDF
Publication Date
Mon Jun 04 2018
Journal Name
Baghdad Science Journal
Designing and Constructing the Strain Sensor Using Microbend Multimode Fiber
...Show More Authors

The microbend sensor is designed to experience a light loss when force is applied to the sensor. The periodic microbends cause propagating light to couple into higher order modes, the existing higher order modes become unguided modes. Three models of deform cells are fabricated at (3, 5, 8) mm pitchand tested by using MMF and laser source at 850 nm. The maximum output power of (8, 5, 3)mm model is (3, 2.7, 2.55)nW respectively at applied force 5N and the minimum value is (1.9, 1.65, 1.5)nW respectively at 60N.The strain is calculated at different microbend cells ,and the best sensitivity of this sensor for cell 8mm is equal to 0.6nW/N.

View Publication Preview PDF
Scopus (2)
Scopus Clarivate Crossref
Publication Date
Thu Jan 01 2015
Journal Name
Iraqi Journal Of Science
Improved Rijndael Algorithm by Encryption S-Box Using NTRU Algorithm
...Show More Authors

With the wide developments of computer applications and networks, the security of information has high attention in our common fields of life. The most important issues is how to control and prevent unauthorized access to secure information, therefore this paper presents a combination of two efficient encryption algorithms to satisfy the purpose of information security by adding a new level of encryption in Rijndael-AES algorithm. This paper presents a proposed Rijndael encryption and decryption process with NTRU algorithm, Rijndael algorithm is widely accepted due to its strong encryption, and complex processing as well as its resistance to brute force attack. The proposed modifications are implemented by encryption and decryption Rijndael

... Show More
Publication Date
Wed Feb 22 2023
Journal Name
Iraqi Journal Of Science
Improved Rijndael Algorithm by Encryption S-Box Using NTRU Algorithm
...Show More Authors

With the wide developments of computer science and applications of networks, the security of information must be increased and make it more complex. The most important issues is how to control and prevent unauthorized access to secure information, therefore this paper presents a combination of two efficient encryption algorithms to satisfy the purpose of information security by adding a new level of encryption in Rijndael-AES algorithm. This paper presents a proposed Rijndael encryption and decryption process with NTRU algorithm, Rijndael algorithm is important because of its strong encryption. The proposed updates are represented by encryption and decryption Rijndael S-Box using NTRU algorithm. These modifications enhance the degree of

... Show More
View Publication Preview PDF