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About Journal

Iraqi Journal of Applied Physics (IJAPLett) is a scientific periodical sponsored and published by the Iraqi Society for Alternative and Renewable Energy Sources and Techniques (I.S.A.R.E.S.T.). The Editorial Board is responsible for the scientific content and other editorial matters relating to the Journal. Manuscripts submitted are first screened by the editors; those on subject matters within the scope of the IJAPLett are sent to an expert referee for evaluation and may be sent to a second reviewer if necessary. This screening process helps to assure an appropriate focus as...
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Linear Adaptive Antenna Array Geometry Effects on Radiation Pattern

A.H. Sallomi; H.M. Mikhlif; S.R. Salim

Iraqi Journal of Applied Physics Letters, Volume 3, Issue 1, Pages 3-6

Over the last few years, the number of subscribers to wireless services has increased at an explosive rate. Smart-antenna technology compared to conventional antenna has the ability to increase the number of simultaneous users, and satisfy the requirements of spectral efficiency, and coverage in wireless communication systems. In this paper the radiation pattern and performance of linear smart antenna array is investigated by considering multiple directions of arrivals of signals. The simulations done confirmed that smart antenna systems using Least Mean Square (LMS) algorithm are able to adjust their pattern to enhance desired signals, and reduce interference. The results also show that smart antenna radiation patterns are related to the number of elements in the array, the inter-element spacing, and amplitude distribution.

Synchronization Scheme for Secured Communications System Based on Chaotic Signals

P.E. Steran

Iraqi Journal of Applied Physics Letters, Volume 3, Issue 1, Pages 7-10

In this work, a numerical investigation of a synchronization scheme for secure communication implemented with nonlinear optical ring cavities is performed. We have demonstrated that masking the information in a chaotic optical wave from a nonlinear ring cavity is technically feasible in a secured communication system. The synchronization is robust and analog information transmission is suitable for the specific case considered.

Quantum Limit Characterization of Signal-to-Noise Ratio using Phase- Shift Keying in Homodyne Detection

N.J. Shukur

Iraqi Journal of Applied Physics Letters, Volume 3, Issue 1, Pages 11-14

In this work, a mathematical treatment for the quantum limit of signal-to-noise ratio (SNR) in homodyne coherent detection was presented. This treatment is based on the case of balanced detection when the incident signal power is much lesser than the local oscillator power when the efficient AC coupling is assumed. The final results were obtained from an analytical expression of SNR dependent of the average number of incident photons and the quantum efficiency.

Polynanocrystalline CuIn3Se5 Thin Film Photoabsorber Layer Produced by Pulsed-Laser Deposition

A. Twerianovich; S. Berzeneev; E. Barissov

Iraqi Journal of Applied Physics Letters, Volume 3, Issue 1, Pages 15-18

Polycrystalline bulk CuIn3Se5 samples for pulsed laser deposition (PLD) targets were synthesized in evacuated quartz ampoules by vacuum melting of 99.999% pure elements. All the polynanocrystalline CuIn3Se5 thin films were deposited onto the glass and glass/ITO substrates by using the PLD technique. The synthesized bulk samples and deposited films were tested by using the XRD analysis. The time–temperature regime of PLD process was developed for preparation of polynanocrystalline CuIn3Se5 thin films with the same composition as the source target. We have used advanced 3-stages temperature-time regime. The thickness of prepared CuIn3Se5 layers was in the range from 300nm till 450nm. The influence of the thermal annealing on the photovoltaic properties and morphology of the as-deposited CuIn3Se5 layers was investigated. The technique of preparation of high photosensitive polynanocrystalline thin CuIn3Se5 films of n-type conductivity was elaborated.

Characterization of E-Mode InZnO Thin Film Transistors Produced by DC Sputtering Technique

G.M.A. Yussif; A.M.H. Enagar; A.S. Megazi

Iraqi Journal of Applied Physics Letters, Volume 3, Issue 1, Pages 19-22

In this work, InZnO and InGaZnO were used as channel layers to fabricate enhancement mode thin film transistors on glass and flexible transparent substrate. The SiO2-In2O3-ZnO system and N2 plasma incorporated IZO film were grown to get a better controllability of the carrier concentration during the film growth. Hydrogen plasma and oxygen plasma effects on the TCO films and the TFTs were investigated.

Profiling of Antimony Diffusivity in Silicon Substrates using Laser- Induced Diffusion Technique

O.A. Hamadi

Iraqi Journal of Applied Physics Letters, Volume 3, Issue 1, Pages 23-26

In this work, profiles of laser-induced diffusion of antimony in silicon were presented. These profiles were considered to attempt enhancing of the silicon-based devices. This enhancement is attributed to the increasing achieved in the diffusion length within a certain layer of the active region in the device. Laser-induced diffusion is a perfect technique for improving the characteristics of electronic devices since it is flexible, contactless, clean and well controlled.

Quantum Limit Characterization of Signal-to-Noise Ratio using Phase- Shift Keying in Homodyne Detection

N.J. Shukur

Iraqi Journal of Applied Physics Letters, Volume 3, Issue 1, Pages 11-14

In this work, a mathematical treatment for the quantum limit of signal-to-noise ratio (SNR) in homodyne coherent detection was presented. This treatment is based on the case of balanced detection when the incident signal power is much lesser than the local oscillator power when the efficient AC coupling is assumed. The final results were obtained from an analytical expression of SNR dependent of the average number of incident photons and the quantum efficiency.

Effect of pH Value on the Photoconductivity of Chemically Deposited CdS Thin Films

S.M.H. Aljawad

Iraqi Journal of Applied Physics Letters, Volume 2, Issue 1, Pages 23-26

Highly photosensitive CdS thin films with photocurrent to dark current ratio (Iph/Id) of ~105 under 300W.m-2 illumination were reported. The films are prepared by an electroless chemical deposition technique. The pH value of the solution used in the electroless deposition of cadmium sulfide thin films has been found to affect the deposition rate, optical transmission, photoconductivity, photoconductivity to dark conductivity ratio Cph/Cd and photocurrent decay time.

Complex Magnetic Investigation of Ferritic Stainless Steel

ros; I. M; A.S. Mahmood

Iraqi Journal of Applied Physics Letters, Volume 2, Issue 1, Pages 9-11

Magnetic Barkhausen noise measurement (MBN) is a relatively new nondestructive detection technique. Its working principle is based on Barkhausen discontinuities or noise when a ferromagnetic material is subjected to a varying magnetic field. MBN is being used to characterise the stress state of a ferritic stainless steel (AISI 430). Other magnetic parameters such as saturation induction (BMax), remnant induction (BR), coercive field (HC) and maximal relative permeability (PMax) derived from the hysteresis loop have also been used to support the results achieved using MBN. Microstructural changes due to cold working and heat treatments were characterized by the applied magnetic measurements. The MBN technique was proved to be a useful non-destructive and quantitative method for microstuctural investigation of the investigated ferritic stainless steel.

Bulk Solid Specimen Shape Dependences in the Molecular, Chemical- Shift Tensor Determinations

S. Aravmdan

Iraqi Journal of Applied Physics Letters, Volume 2, Issue 4, Pages 11-14

In this paper, it has been the effort to systematically document the salient results of the calculations which are taking the course from molecule to material. The ellipsoidal shapes are the ones which have the homogeneous magnetization for homogeneous susceptibility. The computer programs used in this analysis were written FORTRAN. Moreover, a simpler summation procedure could be evolved for the calculation of the shape dependent demagnetization factor.

Characterization of SiC/SiC Composites Used for Power Plant Blanket

K.M.Y. Hasan; N.I.M. Elkashif; S.A.M. Ebrahim

Iraqi Journal of Applied Physics Letters, Volume 2, Issue 1, Pages 27-30

This paper describes the results of an exploratory study of blanket concepts based on SiC/SiC structure and LiPb breeder. An assessment of the performance of these concepts for advanced power plant application is presented, key issues are identified, and constraints relating to the SiC/SiC properties are discussed.

Performance Optimization of Multi-Quantum Wells Laser Used in Optical Communications

S.S. Jasim

Iraqi Journal of Applied Physics Letters, Volume 2, Issue 2, Pages 11-14

In this work, an analytical treatment of some design parameters of multiquantum well semiconductor laser aiming to optimize the performance of such systems is presented. The treatment concentrates on three main parameters; the reflectivity of the front mirror, the effective lifetime of the photon inside laser cavity, and the number of quantum wells in the laser structure. These three parameters relate to several other parameters which impose to achieve design compensation. Such compensation can be simulated by analytical treatments because the characteristics of these lasers have been established well in form of small and large signal solutions. These lasers are increasingly studied due to their characteristic features in optical communications architectures, low-dimensioned photonics and optoelectronics devices.

Computation of Optical Energy Gap of Cu2O Thin Film: Theoretical Estimation

N.F. Habubi; K.A. Mishjil; H.G. Rashid; B.G. Rasheed

Iraqi Journal of Applied Physics Letters, Volume 1, Issue 1, Pages 21-23

Thin films of cuprous oxide Cu2O have been prepared using spray
pyrolsis technique. Experimentally, the optical energy gap of Cu2O was
about 2.2eV. To achieve and estimate an accurate Eg value, there was
problem in the selection of exact tangent point. To overcome this
problem, Newton-Raphson method and mean-value theorem were used.
It was found that the mean-value theorem can predict correlated nearly
satisfactory Eg value than the other method.

Effect of Chirping on Received Pulse Shape in Optical Fiber Communications

A.A.K. Hadi; H.S. Dawood; B.A.M. Bader; R.O. Mahdi

Iraqi Journal of Applied Physics Letters, Volume 2, Issue 2, Pages 7-10

In this work, the effect of chirping on the pulse broadening and wavelength shift in the optical fiber communications was studied. A numerical analysis based on tracing the pulse propagating through an optical fiber was presented to determine the role of chirping in pulse broadening. Consequently, the wavelength shift resulted from the chirping effect was deduced analytically.

Characterization of SiC/SiC Composites Used for Power Plant Blanket

K.M.Y. Hasan; N.I.M. Elkashif; S.A.M. Ebrahim

Iraqi Journal of Applied Physics Letters, Volume 2, Issue 1, Pages 27-30

This paper describes the results of an exploratory study of blanket concepts based on SiC/SiC structure and LiPb breeder. An assessment of the performance of these concepts for advanced power plant application is presented, key issues are identified, and constraints relating to the SiC/SiC properties are discussed.

Study on Compensation of Thermal Stresses in the Fabrication Process of Thin-Film Transistor

A.A. Khalaf; M.O. Ghafil; S.M. Alrawi

Iraqi Journal of Applied Physics Letters, Volume 1, Issue 1, Pages 28-30

It is essential to align masks without tolerance in every deposition step
when fabricating thin-film transistors (TFTs) on a polymer substrate.
However, the shrinkage of the polymer substrate due to thermal effect
may arise during the deposition process. We observed the variation of
shrinkage as a function of the annealing temperature. It was found that
the substrates keep shrinking up to a critical temperature and stay the
same above that point. The thermal treatment was conducted on
substrates polycarbonate (PC), the polyarylate (PAR), and poly(ether
sulfone) (PES). After predeposition annealing, the shrinkage was
prevented but deformation was observed on the surface. An inorganic
thin film with a different thermal expansion coefficient was employed to
remove the deformation and this resulted in the elimination of strain.

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