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دراسة نظرية للتركيب الالكتروني والخواص المغناطيسية الحجمية والسطحية لسبيكة هيوسلر الرباعية CoXMnSi (X:Nb,Ru) == A Theoretical Study of Electronic and Magnetic Properties of the Bulk and Surface of the Quaternary Heusler Alloy CoXMnSi (X:Nb,Ru)

Author name: عمار عبد الجبار كاظم الحسن
Supervisor name: جبار منصور الزيادي
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Education For Pure Sciences
Language: Arabic
University location: Basrah
First pages:

الامن البصري باستخدام مصادقة العد الفوتوني لمتعدد العوامل المشفر == Optical Security Using Photon- Counting Multifactor Encryption and Authentication

Author name: عماد عبد الزهرة محمد
Supervisor name: Haitham L. Saadon | Hassan H. Mohammed
General topic: Physics
Specific topic: Laser Physics and Electro-optics
Degree: Master
University: University Of Basrah - College Of Science
Language: English
University location: Basrah
First pages:

الاستجابة البصرية اللاخطية باستخدام الخواص البصرية الحرارية لصبغة بلورة الرفامبين الحمراء البنية == NONLINEAR OPTICAL RESPONSE USING THERMAL OPTICAL PROPERTIES OF DYE RED-BROWN REFAMBIN CRYSTAL

Author name: علياء عبد الجبار جري
Supervisor name: حسين علي بدران
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Education For Pure Sciences
Language: Arabic
University location: Basrah
First pages:

دراسة التاين الضوئي والعمليات الاشعاعية للذرات والايونات باستخدام طريقة مصفوفة البعد النسبية == Studying of the Photoionization and Radiative Processes of Atoms and Ions by Using Relativistic R-matrix Method

Author name: عقيل هاشم حسين
Supervisor name: فلحي عبد الحسن علي | علاء عبد الحسن خلف
General topic: Physics
Specific topic: Atomic Physics
Degree: Doctorate
University: University Of Basrah - College Of Science
Language: English
University location: Basrah
First pages:

تحضير خلطة البولي يورثين ايبوكسي النقية والمشوبة بمضافات محلية ودراسة بعض خواصها الفيزيائية وتطبيقاتها كبوليمر مضاد لبعض الكائنات الجرثومية == Preparation mix polyurethane - epoxy pure And tinged with local Avadavat ,study s ome of Physical Properties And It's Application as anti-microbial polymer

Author name: ريام احمد مطشر
Supervisor name: خالد ابراهيم عجيل
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Education For Pure Sciences
Language: Arabic
University location: Basrah
First pages:

مساحة المقطع الراداري للاجسام الموصلة المطلية بطبقة عازلة والمتناظرة محوريا == Radar Cross Section for Coated Bodies of Revolution

Author name: رؤى رحيم هيلان
Supervisor name: زكي عبد الله احمد | عقيل سامي طاهر
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Science
Language: Arabic
University location: Basrah
First pages:

تحضير ودراسة الخواص البصرية والكهربائية اورثو - مشترك - للبوليمر المشترك بولي (انيلين اورثو توليدين ) النقي - مشترك - انسدين والمشوب وتطبيقاته في الخلايا الشمسية == Preparation and Studying the optical and electrical properties of Copolymer poly(Aniline-CO-O Ansidine -CO-O Toluidine)pure and doping and It's application as Solar Cell

Author name: افراح حسين صاكي
Supervisor name: حسين فالح حسين
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Science
Language: Arabic
University location: Basrah
First pages:

دراسة بعض الخواص الفيزيائية للبولي بارا انسدين المحضر بطريقة كيميائية والبوليمر المشترك الجديد PU/Rh6G == A Study For Some Physical Properties Of The Chemically Synthesized Poly Para Anisidine(PPAN)and new copolymer(PU/Rh6G

Author name: احمد سعود عبد الخنجر
Supervisor name: كريمة مجيد زيدان | علي قاسم عبد الله
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Science
Language: Arabic
University location: Basrah
First pages:

دراسة نظرية في التاثيرات البرمية الحرارية للنقطة الكمية في مجال مغناطيسي == Theoretical Study in the Thermospin Effects for the Quantum Dot in a Magnetic Field

Author name: ريمان جمال جاسم
Supervisor name: جنان مجيد المخ
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Education For Pure Sciences
Language: Arabic
University location: Basrah
First pages:

دراسة نظرية الاستطارة الالكترونية والبوزترونات لبعض الذرات الحرة والايونات الموجبة عند طاقات مختلفة == A theoretical study of electrons and positrons scattering for some free Atoms and Positive Ions at Different Energies

Author name: احلام خضير ياسر
Supervisor name: فلحي عبد الحسن علي | عقيل هاشم حسين
General topic: Physics
Specific topic: Electronics Physics
Degree: Master
University: University Of Basrah - College Of Science
Language: Arabic
University location: Basrah
First pages:

دراسة نظرية للخواص الالكترونية والمغناطسية للحجم والسطح للمركبات MBi (M=V, Cr, Mn) والحد الفاصل MnBi/HgTe == A Theoretical Study of electronic and magnetic properties of the bulk and surface of compounds MBi (M= V, Cr, Mn) and the interfaces of MnBi/HgTe

Author name: نهاية هادي عبد الوهاب
Supervisor name: جبار منصور الزيادي
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Education For Pure Sciences
Language: Arabic
University location: Basrah
First pages:

تحضير خلطة البولي يورثين ايبوكسي النقي والمشروب بمضافات محلية ودراسة الخواص الميكانيكية والخواص العازلية == Preparation mix polyurethane - epoxy pure And tinged with local Additives ,And Study Some of Mechanical and Dielectric Properties

Author name: محمد جاسم سلطان
Supervisor name: خالد ابراهيم عجيل
General topic: Physics
Specific topic: Semiconductors
Degree: Master
University: University Of Basrah - College Of Science
Language: Arabic
University location: Basrah
First pages:

دراسة التاثيرات النسبية و غير النسبية على المقاطع العرضية للاستطارة المرنة للالكترونات من الذرات

Author name: علي خيري بدر الاسدي
Supervisor name: علاء عبد الحسن خلف
General topic: Physics
Specific topic: Electronics Physics
Degree: Master
University: University Of Basrah - College Of Science
Language: Arabic
University location: Basrah
First pages:

تحضير وتشخيص ودراسة الخصائص البصرية والكهربائية للبوليمرات المشتركة من بولي كحول الفينيل المطعم ببعض الاصباغ العضوية وتطبيقاتها في الخلايا الشمسية == Synthesis , Characteristic and Study the Optical and Electrical Properties of Polycohol Alvinyl Grafted Some Organic Dyes and Their Application in Solar Cell

Author name: زينب علي عبد الرسول الربيعي
Supervisor name: علي قاسم عبد الله
General topic: Physics
Specific topic: Solar Energy Physics
Degree: Master
University: University Of Basrah - College Of Science
Language: Arabic
University location: Basrah
First pages:

الخواص البصرية والكهربائية ومحدد القدرة البصري لبعض الصبغات العضوية المشوبة لاغشية البوليمر

Author name: رغد جبار صدام
Supervisor name: عماد الدين حسين علي السعيدي
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Science
Language: Arabic
University location: Basrah
First pages:

تحضير البوليمر الموصل بولي (ارثوا - تولدين) ودراسة الخصائص البصرية والكهربائية له واستخدامه في تصنيع الخلايا الشمسية == PREPARATION OF CONDUCTING POLY (O - TOLUIDINE) AND STUDY OF ITS ELECTRICAL AND OPTICAL PROPERTIES FOR APPLICATION AS A SOLAR CELLS

Author name: حسين فالح حسين اللعيبي
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: University Of Basrah - Faculty Of Education
Language: Arabic
University location: Basrah
First pages:
Abstract: The present study include the preparation of poly (O - Toluidine), by the chemical polymerization, then doped with HCl, and P - toluene sulphonic acid.The polymer solution deposited on glass, interdigitated finger electrode, and silicon wafer by the use of spin coating technique, in order to study electrical and optical properties as well as electronic applications in the fabrication of solar cells. The prepared samples were treated thermally before the measurement took place. Addition, a study was made of the effect of dyes on solar cells, (RhB, Flu, CuPc, and PbPc ) deposited on poly(O - Toluidine) and doped by p - toluene sulphonic acid (POT - PTSA). The thickness of the samples is measured by the use of Ellipsometry spectroscopy. The polymer thin films prepared were analysized by the use of (FT - IR) and Raman spectroscopes to determine the functional groups of the chemical bonds. To identify the nature, the structure of the surfaces of the prepared samples and to measured the partial size of the grain Atomic force Microscopy AFM insistent were used. The optical properties of the thin films prepared were studied including recording the absorption spectroscopy for wavelengths of (300 - 900 nm). The absorption coefficient and the forbidden energy gap to transmission directly were measured as well as the refraction index (n), extinction coefficient (k), dielectric constant ε, as well as, the optical constant represented by single oscillator energy (Eo), dispersion energy (Ed), moment of dielectric constant (M - 1, M - 1 3), non linear optical susceptibility (χ3) were determined.The electric conductivity was studied and it was found that the thin films correlate with the ohmic behaviour at the measured volts range (1 - 100V) for the polymers (POT, POT - HCl, POT - PTSA, and POMA). The effect of the temperature on the electric properties of these thin films is also studied. The study shows that the electric conductivity increases with the increase of temperature, where all the samples were found to show a negative thermal coefficient of resistance which is a characteristics of semi - conductive material.The effect of doping with HCl and p - toluene solphonic acid on electric conductivity was studied and found to increase to (2.46x10 - 5 S.cm - 1) while the conductivity of the polymer doping with HCl increases to (7.59x10 - 6 S.cm - 1) compared to the pure polymer (1.49x10 - 7 S.cm - 1). This study shows that the activation energy in the pure polymer is (0.313eV) and decreases when the polymer was doped with PTSA, HCl to (0.211 eV) and (0.235 eV) respectively.For the electronic application of prepared polymers (POT, POT - HCl, POT - PTSA, and POMA) a solar cells were constricted by using n - type silicon wafers and different electrode from gold and aluminium. The optical properties of the solar cell under the effect of the light equivalent to that of the sun and which falls vertically on the sample were studied ; it is practically found that, the highest efficiency obtained is (2.55 %) for the polymer (POTPTSA). The effect of thickness on the solar cell efficiency is also studied where it is found that the highest efficiency is about (2.55%) at thickness (35 nm). The electric properties of the solar cell were studied at different intensity (10,25, 50, 100) mW/cm2 and the efficiency reaches its maximum (4.88) when the intensity of the incident light is equal to 10 mW/cm2. It is observed practically that the efficiency of all cells decreases when dyes are added to the polymer (POT - PTSA). The exposure of the solar cell of the polymer (POTPTSA) to normal weather conditions was tudied for more than two monthswhere it is observed that the cell efficiency falls from 2.55 to 1.18 after two weeks of exposure. Then it reached constant value of 0.88 for two months of time exposure

تحديد النشاط الاشعاعي للنظائر المشعة 137Cs,134Cs,I131,40Kفي الاغذية المستهلكة في مدينة البصرة جنوب العراق == Radiation activity determination of 137Cs,134Cs,I131,40K and in food consumed in Basrah South of Iraq

Author name: مروة جواد كاظم راضي
Supervisor name: عبد المنعم خليل الكامل | علي عبد عباس الربيعة
General topic: Physics
Specific topic: Nuclear and Environmental Physics
Degree: Master
University: University Of Basrah - College Of Science
Language: Arabic
University location: Basrah
First pages:
Abstract: SAM 940TM detector has been used to detect and identify the radioactive isotopes (Radio - Isotope Identification (RIID)) at low levels of gamma rays emitted from food materials.Six samples of fresh milk have been pick out for six locations in Basrah. Ten samples of imported milk powder have been taken into account. Ten samples of lentils, rice, coffee and tea have been taken into account.Eight samples of mineral water, one of distilled water and one sample of piped water; the last one has been picked out from the net distributed water at physics department building in college of science university of Basrah.The results of our study show that, the annual effective dose for the radioactive potassium ????40 in food materials of the highest value. For local fresh milk is (0.216,0.529)mSv/y for adults and children respectively. It is of these samples have been taken from Zubair city, and its less value is (0.076,0.186)mSv/y for adults and children respectively. These samples have been taken from Abuo Al Kasseb. As for the imported milk powder, the highest value is (0.556,1.349) mSv/y for adults and children respectively. The sample is related to Al - munash milk from New Zealand, and less value is (0.272,0.660)mSv/y for adults and children respectively. The sample is related to modhash imported milk powder from Oman.For rice, the highest value is (0.303,0.636) mSv/y for adults and children respectively. The sample is related to Mahmood rice from India, and less value is (0.149, 0.313) mSv/y for adults and children respectively. That is for Galaxy rice imported from India.As for lentils, the highest value is (0.029 ,0.061) mSv/y for adults and children respectively. The sample is related to Wade al akdar lentils from Syria, and its less value is (0.020,0.042)mSv/y for adults and children respectively for Urbak lentils imported from Tukey. For water, the highest value is (0.189, 0.398) mSv/y for adults and children respectively for distilled water and Janaan drinking water from Baghdad. Its less valueis (0.183, 0.385)mSv/y for adults and children respectively for Aquafina drinking water imported from Kuwait.For coffee, the highest value is (0.041) mSv/y for adults for two samples from Brazil and one sample from Spain and other produce from Poland. Its less value is (0.019)mSv/y from European Union production. For tea, the highest value is (0.019, 0.039) mSv/y for adults and children respectively for Jant almunaash and Gazalian samples tea, its less value is (0.008,0.015)mSv/y for adults and children respectively for Alwaza, Mahmood and Baiet alteb samples tea imported from Sri Lanka.The annual effective dose of Iodine ????131 , Cesium ????????134 and Cesium ????????137 in lentils, rice, coffee, tea, mineral water, distilled water and piped water have been carried out and the results are listed in thesis.

تقييم اداء تصاميم جديدة لسخان الماء الشمسي في مدينة البصرة30.5°N == Evaluation of new designs of solar water heater in Basrah city 30.5° N

Author name: كوثر كاظم منخي
Supervisor name: نوري حسين نور الهاشمي | جاسم مهدي الاسدي
General topic: Physics
Specific topic: Solar Energy Physics
Degree: Doctorate
University: University Of Basrah - College Of Education For Pure Sciences
Language: Arabic
University location: Basrah
First pages:
Abstract: The main goal of the current study is the benefit of solar energy as the origin of any renewable energy for producing a hot water through multiple solar collectors each one with overall capacity about 26 liter so that, these collectors arranged in sequential order within the construction of the house without affecting the artistic aspects of the house. These collectors will capable of providing the house the needs of hot water for domestics use especially during the winter season. It will reduce the amount of energy such as electricity and or kerosene or any other source of energy that usually used in Basrah.The present study is included the design and manufacture of seven models of solar collectors. The tools that have used into manufactured of these collectors are some cheap materials that are available in Basrah markets. These models are differ from each other by some aspects with additions properties. The thermal performance and efficiency have a test and then choose the best one in order to use it in four different modern designs of solar heaters.the thermal performance of the manufactured heaters models are tested by calculate the amount of hot water supply under difference weathers conditions in the city of Basrah, which sorts as a large abundance of solar radiation. It also test two types of arrangement of difference parts of heaters. The practical test has been proven the advantage of linking hot water reservoir tank with cold water and then linking the whole system with the hot water tank. This arrangement will allow of gradual warming of the water, which allows the consumer get the hot water directly from the system and not from the reservoir. This study include what is called a feedback arrangement system in order to increase the benefit from solar radiation. In this case, the hot water will recycle to allow for moreexposure to solar radiation repeatedly, that in the case of non - use or the case of little use.All the experiment Steps carried out on the roof of the department of physics building's in the college of education for pure Sciences, Basrah university in the northern city of Basrah, located at latitude 30.50 N and longitude 47.80 E during the winter season 2013 - 2014. Al thought this winter characterized by abundant of rain and clouds the models No.5 shows very good results interm of high temperature of hot water and the amount of it. The temperature was reach (900 C). In addition the model No.4 which depend on the technique of feedback idea shows a good result interm of the amount of hot water produce which reach (146 liter) at a temperature about (500 C) with in only five hours starting at 10 : 00 am until the 2 : 00 pm.In order to develop the optimum dimensional measurements of the solar collectors a mathematical model was developed to predict the output temperature of hot water from the solar collectors or from the radiator in general for different dimensions. This model is working successfully and achieved data that in comparable with our experimental ones. The experimental results have been analyzed theoretically to compare the performance of all solar collectors of the heaters, in different weather conditions and in a same time.

درجة الحرارة المميزة وطاقة الاثارة الدنيا لليزر النقطة الكمية الشبه الموصل == Characteristic Temperature and Lowest Excitation Energy of Semiconductor QD laser

Author name: غيث منور علي
Supervisor name: رائد محمد حسن
General topic: Physics
Specific topic: Laser Physics and Electro-optics
Degree: Master
University: University Of Basrah - College Of Education For Pure Sciences
Language: Arabic
University location: Basrah
First pages:
Abstract: In this work, we have studied important theoretical relationships in Semiconductor Quantum Dot Laser (QDL) Characteristics.The study is based on theoretical model equations that are derived from the rate equations. The equations were applied on experimental parameters of continuous - wave QDL GaInP/InP at 1.55μm wavelength to get theoretical simulation of the characteristics of this laser type.We also studied the temperature effect on the internal losses and the impact of these losses in determining the characteristics of the temperature of QD. The results were presented within two cases; the first is when there are no internal absorption losses and the second where there is no existence of these losses. Also, we studied the effect of ambient temperature on the characteristics of temperature for each of QD and OCL.The lowest excitation energy of QD has been studied in two control cases : with surface density of QD and with cross - section of internal losses.Throughout changing many systems and control parameters, the effects of these parameters have been studied according to the different kinds of relationships. In this research, we have studied the parameters : Surface density of QD, mean size of QD, optical confinement layer, radiative constant for OCL material, spontaneous radiative recombination time, root mean square of QD size fluctuations, cavity length and mirrors reflectivity.Some of the results in this work were compared with other experimental results of other researchers who applied the QDL model and showed a good matching.

التقنين الاشعاعي البيئي للمياه الجوفية في غرب محافظة البصرة باستخدام تقنية التالق الحراري == Environmental Radiation Dosimetry of Groundwater in West of Basra Governorate using Thermoluminescence Technique

Author name: سيف قاسم هلال
Supervisor name: رياض جاسب ابو الهيل
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Education For Pure Sciences
Language: Arabic
University location: Basrah
First pages:
Abstract: This study includes calculation the dose rate of emitted gamma - rays from groundwater taken from different locations in the Basra govemorate by use of thermoluminescence technique . it emphasis on the the characteristics of TL - reader ,TL - dosimeter (calcium fluoride) to know the suitability of these systems for environmental monitoring. It is found that the zero dose reading for calcium fluoride is 0.18 m rad .It is also found that most dosimeters of the same materials have nearly equal sensitivities and that all thebatches have high uniformity which makes them capable for environmental use. Experimental observations have indicated that there is linear relation between response and dose for the material which qualifies it for measuring doses within the low dose range. The variations in the response of the TL - reader using internal light source have also been investigated ,it is found that TL - reader has high stability .The fading in a environmental field for calcium fluoride is 7% in one month.Making sure that these systems are suitable for environmental monitoring programing ,calcium fluoride has been used for measuring gamma - rays emitting from natural background radiation ,it is foundthat the natural dose rate of gamma - rays emitted from the locations : Albrjisiya, khor aizubair, Safwan, Jabal Sanam, Um Qasr, Um Eanij and Al - lahees are (5.80,6.41, 5.32, 5.25,5.26,4.60 and 4.86) μrad/h receptivity . Thus, the dose rate of radiation emitted From ground water of province of Basra is 5.35 μ rad/h . the results proved that the inhabited area ling within the environmental monitoring satiations are the area in which the radiation is natural and that the rate that the human being exposed equal 11.5μrad/h which considered naturalexposure limit.

تحضير وتشخيص بعض البلورات السائلة وخلائطها الثنائية البلورية السائلة ودراسة بعض خواصها الفيزيائية == Preparation & Characterization of some liquid crystals and Binary liquid crystalline mixtures and study some of their physical properties

Author name: زينب نديم مطشر
Supervisor name: اياد جاسم الحجاج
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Science
Language: Arabic
University location: Basrah
First pages:
Abstract: study included as a first step the preparation of compound 4 - heptyloxy benzaldehyde and derivatives by linking alkoxy series with the aldehyde, and in the second step was to prepare Schiff base compounds through interaction of equal moles of the compound 4 - heptyloxy benzaldehyde with some primary amines with different polar groups, and in the third stage was to prepare mixtures from the Schiff base compounds resulting from the second step,and we obtained five liquid crystalline mixtures at low temperatures and some of them close to room temperature, and then the chemical structures was chacterized and the absorption bands for functional groups was given by FTIR spectroscopy scan . A microscope with polarized light (POM) and a differential scaning calorimeter (DSC) was also used to study the liquid crystalline phases for individual compounds, as well as binary liquid crystalline mixtures and then a discussion of changes taking place at phase transition temperatures for individual liquid crystalline compounds as well as their binary mixtures , as characterized by these mixtures it owns a wide range of temperatures and some are close to room temperature ranging between (22.1 - 53.1 ℃). we has been studying some of the physical properties of these mixtures and compare them with the pure liquid crystals to see what has been achieved to improve these properties by studying the electrical properties (conductivity and dielectric ), as well as the activation energy , we has also been studying the photoelectric effect and determine the threshold voltage in the cases of parallel and vertical alignments , and the study shown a variation in the dielectric behaviour of binary liquid crystalline mixtures of remarkable increase compared to individual liquid crystalline compounds either the positive or negative dielectricanisotropy , ranging from ( - 1.320 - 2.234), while the variation in the electrical conductivity of binary mixtures of liquid crystal range (0.138 - 0.351 (ohm.m) - 1, and finally studied photoelectric effects for individual liquid crystalline compounds, as well as binary liquid crystal mixtures show that liquid crystalline mixtures have seen a clear decline in the threshold voltages (1.3 - 3.9Volt

دراسة نظرية لانتشار نبضة كاوسية في الياف البلورة الفوتونية والعوامل المؤثرة فيها == Theoretical Study of the Propagation Gaussain Pulse in Photonic Crystal Fibers and the Parameters Influencing it

Author name: دعاء حسين هاشم
Supervisor name: حسن عبد الله سلطان
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Education For Pure Sciences
Language: Arabic
University location: Basrah
First pages:
Abstract: In this thesis the propagation of short Gaussian pulse in Photonic Crystal Fibers (PCFs) are studied, the effect of the fiber parameters on the pulse like the absorption, dispersion and nonlinearity studied also.Nonlinear Schrodinger Equation (NLSE) was solved numerically using the spectral or Split - Step Fourier Method (SSFM) to determine the pulse spatio - temporal evolution.The study includes the effect of the photonic crystal arrangement especially the holes number, hole - hole spacing and holes dimeter on the effective refractive index and the dispersion of the photonic crystal fiber.The Nonlinear Schrodinger Equation (NLSE) was solved using the Finite differences in the frequency domain (FDFD) method.The two zeros dispersion were studied to calculate the zero dispersion wavelength (ZDW) by applying the international golden ratio (1.16180339887) for the ratio of the hole - hole spacing to the holes dimeters.The study shows that the pulse propagation depends strongly on the absorption, dispersion and nonlinearity of the PCF, and the pulse wavelength must be near the ZDW to ensure the propagation with little loses.The dependence of the nonlinear refractive index, the dispersion and the ZDW of the PCF were proved.The study shows that the golden ratio can be used to have two ZDWs, and a new ratio of hole - hole spacing to the hole dimeter equal to 2 can be used to achieve two ZDWs.

حساب كثافة الحاملات في طبقة الحصر البصري واشغال الحاملات المحصورة في منظومة ليزر النقطة الكمية نوع GaInAsP/InP == Calculating the Carrier Density in OCL and Confined Carrier Occupation in Quantum Dot Laser System Type GaInAsP/InP

Author name: ایمان ذیاب شرشاب
Supervisor name: رائد محمد حسن
General topic: Physics
Specific topic: Laser Physics and Electro-optics
Degree: Master
University: University Of Basrah - College Of Education For Pure Sciences
Language: Arabic
University location: Basrah
First pages:
Abstract: In this work, we have studied many control parameters effect which plays an important role to determine the density concentration of carriers in the Quantum Dot Laser (QDL) system. Our study is based on theoretical model equations which derived from the rate equations. The equations were applied to the GaInAsP/InP QDL with wavelength 1.55μm. We produce a theoretical simulation and analytical solution of the equations by a Mathematical program.Theoretical equations are used to study the effect the parameters by controlling the value of each : the carrier's density and occupancy of the Level of a carrier confined in a QD. There are two cases : when the cross - section of the internal absorption losses has a influential amount and a nather it case when approaching zero border. As well as, we study the impact of the parameters on the threshold current density and its compounds. In addition, we study the role of these parameter to determining the maximum temperature of QDL operation through effect on temperature rang of the system.The temperature effects on the carriers’ activities in the system are studied, whereas the characteristics temperature of QDL has been studied in the two cases : with / without internal losses.The effects of structure and control parameters are applied to Study many factors. Such as : surface density of QD, mean size of QDs, optical confinement layer, spontaneous radioactive recombination time and resonator losses.

دراسة تاثير جهود المصيدة على سلوك الدالة الموجية في تكثيف بوز اينشتاين == Study influence of the trapping potentials on the behavior of the wave function in Bose - Einstein condensation

Author name: وليد حميد عبد المالكي
Supervisor name: خالد محمد جياد الموسوي | خالد محمد جياد الموسوي
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Science
Language: Arabic
University location: Basrah
First pages:
Abstract: This dissertation have been studied and analyzed the wave function behavior under trapping potentials that are usually used in experiments which led to formed Bose - Einstein condensation in ultra cold gases. The wave function behavior is dealt with under the effect of three types of potentials : the Harmonic oscillator, the double well, and the Optical Lattice. These are used individually, overlapped together, and when two different kinds are shed on each other in an orthogonal form. Besides, factors and variables that have major or minor roles in potentials the distribution that determine the wave function behavior is discuss in this dissertation.And study parameter ???????? range of effect on the nature of the Harmonic oscillator trapping potential and the Wave Function distribution, this factor effect is studied under the effect of the Harmonic oscillator Trap. As well as, studying this parameter effect on the Wave function behavior under the effect of other three types of potential traps used in Bose - Einstein condensation which are : the Optical Lattice potential overlapped with the Harmonic oscillator potential, the Optical lattice potential orthogonally shed on the harmonic oscillator potential. Also, studied the wave function behavior under the effect of the double well potential when the range of distribution centre is ∓0.5 and when the distribution centre increases to ∓2.And also discussed the effect of the nonlinear G on the wave function behavior under the effect of the Harmonic potential in terms of value and distribution. Through studying under the effect of the Harmonic potential, it have noticed that there is a linear relation between the energy and the chemical voltage at the centre of the trap as well asbetween the wave function and Energy. Yet, the linear relation is not exist between Energy and the frequency rate ???????? as well as between the wave function and the chemical potential. While there is a nonlinear relation exist under the effect of the optical lattice potential overlapped with the Harmonic potential at the centre of trap as well as the relation is exist between the wave function and the energy at the centre of the trap. It is noticed that when the optical lattice potential orthogonally shed on the Harmonic potential a linear relation exists between the energy and the chemical potential with anisotropy value and this linear relation becomes more clear at high value of anisotropy while the wave function behavior increases exponentially with anisotropy values. Furthermore, we have studying the effect of Factor ???????? and Factor ???????? on the Wave Function behavior under the harmonic potential trap plus the optical lattice potential .

دراسة مقارنة بين ليزرات الابار الكمية والنقاط الكمية == Comparative Study Between Quantum Wells and Quantum Dots Lasers

Author name: وطن حمود جبر
Supervisor name: جاسب عبد الحسين مشاري
General topic: Physics
Specific topic: Laser Physics and Electro-optics
Degree: Master
University: University Of Basrah - College Of Education For Pure Sciences
Language: Arabic
University location: Basrah
First pages:
Abstract: In the work we present a comprehensive comparison between the dynamics of quantum well and quantum dot semiconductor lasers working autonomously using two models, the first describe the temporal variation of carriers and photon densities respectively in the quantum well lasers and the second describe the carriers occupancies in the wetting layer and quantum dot and photon occupancy in the quantum dot lasers .The study was carried out on the delay time and level of the dc part of their power under the effect of the many parameters that appeared in those models. Both lasers dynamics were studied in the presence of injection current modulation which enhances lasers power range from periodic to chaotic one with varieties of periodic states such as period.1, period.2, period.3, period.4 and period.6. Developed chaos was noticed to occur.We propose and investigate a simple method to obtain complex output power from both lasers via pulse shaping of the injection current. During the three methods studied we noticed similarities and discrepancies in both lasers dynamics.
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