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ليزر الليف المشوب المتعدد الطول الموجي ذي مفتاح عامل النوعية المعتمد على الجسيمات النانوية كممتص مشبع == Multiwavelength Q-switched Doped Fiber Laser Based on Nanoparticle Saturable Absorbers

Author name: علي عبد الله سلمان
Supervisor name: عبد الهادي مطشر الجنابي
General topic: Laser Science
Specific topic: Laser Applications in Electronics and Communications Engineering
Degree: Doctorate
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad

التحقق من بروتوكول توزيع المفتاح الكمي بطريقة عدم الاعتماد على اجهزة القياس

Author name: احمد اسماعيل خليل
Supervisor name: شيلان خسرو توفيق
General topic: Laser Science
Specific topic: Laser Applications in Electronics and Communications Engineering
Degree: Doctorate
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:

Generation of switchable and tunable wavelength erbium - doped fiber laser using ring cavity configuration

Author name: ورود
Supervisor name: Abdul Hadi M. Al-Janabi
General topic: Laser Science
Specific topic: Laser Applications in Electronics and Communications Engineering
Degree: Doctorate
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:

ليزر الليف البصري ذي النبضة القصيرة المعتمد على اكاسيد المعادن الانتقالية النانوية كممتص مشبع

Author name: سارة كاظم محسن الحيالي
Supervisor name: عبد الهادي مطشر عبد الجنابي
General topic: Laser Science
Specific topic: Laser Applications in Electronics and Communications Engineering
Degree: Doctorate
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:

دراسة سطح المعدل بليزر فلوريد الاركون كمتحسس لتشتت رامان == Investigation of modified CR39 surface by ArF laser as an SERS sensor

Author name: رنا محمد طه البياتي
Supervisor name: حسين علي جواد
General topic: Laser Science
Specific topic: Laser Applications in Electronics and Communications Engineering
Degree: Doctorate
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:

قياس وتحليل الخسائر لموجات الموجع ذوات الفتحة المصنعة من سليكون على عازل == Measurements and Analysis of The Losses for Fabricated SOI Slot Waveguides

Author name: ميثم نعيم صالح
Supervisor name: مازن مانوئيل الياس
General topic: Laser Science
Specific topic: Laser Applications in Electronics and Communications Engineering
Degree: Doctorate
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:
Abstract: An interesting silicon photonics component is the slot waveguide. The discontinuity of the normal component of the displacement vector can be used to affect guiding of the majority of the electric field energy in a narrow low index gap when the field is polarized parallel to the silicon surface, that is, perpendicular to the silicon confining walls. By infiltrating nonlinear material into such a gap, one can simultaneously confine electric and optical fields achieving a high efficient optical modulation or switching that is becoming more desirable on optical communication. An array of 200 Silicon - on - Insulator (SOI) slot waveguide devices of varying slot widths, ribs widths, taper lengths and slot lengths are fabricated in each cell of a wafer fabricated at a commercial foundry. The cells are cleaved into individual chips after fabrication. Some chips are coated with thin films of polymers that fully infiltrated the slots. Measurements that consisted on spectral loss are made on the grating coupler waveguide devices of both coated and uncoated chips. Individual devices exhibited insertion losses varying from several dB up to values so great that the response is below the noise floor of the optical spectrum analyzer employed as a receiver. The chips that failed in the transmission test are primarily uncoated ones. Nominally identical devices on different chips exhibited nominally identical behavior. A commercial software program is used to simulate each of the structures that is included in the 200 devices test. The simulations are seen to show a degree of qualitative agreement with the experimental results. Comparison of the experimental measurements and the simulation results indicates that the loss inherent in a slot waveguide is quite low. Near loss free couplers from ridges to slots are achievable in case of coated devices, whereas the situation is different in case of uncoateddevices where a lot of energy is dissipated through the substrate. Use of a surface roughness model indicates that the excess loss that slots exhibit with respect to a ridge mode counterpart arise almost solely from surface scattering off the surface roughness. The increased loss in the case of the slot guide arises from the higher electromagnetic energy density at the surface of the guide due to the electric field discontinuity that is employed as a guidance mechanism in slot modes in contradistinction to ridge modes that are index - guided. Conclusions include some speculation as to the limits on the loss that can be achieved by variation the design of slot guides without any improvement in surface roughness over what is now available with fabrication in commercial foundries.

التحقق من تاثير عدم استقرارية بلاتو - رايلي في عملية سحب ليف شبه المواد انديوم - بوليمر == Investigation of the influence of the Plateau - Rayleigh instability in fibre drawn indium - PMMA metamaterial

Author name: احمد عبد الكريم علي
Supervisor name: عبد الهادي مطشر الجنابي
General topic: Laser Science
Specific topic: Laser Applications in Electronics and Communications Engineering
Degree: Doctorate
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:
Abstract: Metamaterial is a synthetic composite material with a structure such that it exhibits properties not usually found in natural materials. Fibre drawing method has been used in producing Poly - methyl methacrylate (PMMA) - indium wires metamaterials. PMMA and indium are having relatively the same glass transition temperature making them suitable for co - drawing. The fiber filaments must be drawn to smaller diameters to shift the metamaterials response to higher frequency. At these dimensions the metal filaments inside the fiber become unstable and break - up at random intervals. This instability is due to a phenomenon known as the Plateau - Rayleigh InstabilityWell known Tomotika model for the growth in the varicosity in the surface of fluid extended inside another fluid was modified to describe the fluctuations (instability) of inner core diameter for metamaterials drawing inside radiative furnace. Modified Tomotika model was used to investigate the instability growth of the indium wire diameter produced by co - drawing of indium metal embedded in a PMMA polymer.The critical parameter for the wire breaks is the wavelength of perturbations. A MATLAB model was used to describe a small drawing ratio (neglecting the wavelength of fluctuations effect). The experimental and modeling results are almost match when a very small temperature variation occurred. So the observed fluctuations in diameter can be reconciled with the Plateau - Rayleigh instability.For larger fluctuations (large drawing ratio) the wavelength of fluctuations was analyzed and sequential breakup on different length scales was observed. We infer limits to wire dimensions that can beachieved using the chosen material system and identify a path for extending drawing methods to fabricate smaller wires.Finally, simulation for deep subwavelength wave propagation inside wire metamaterials depending on the unit cell manipulation was performed. CST microwave studio software had been used to simulate wave propagation inside linear and 90o corner waveguide as well as equal arms beam splitter (50/50). It’s applicable to waveguiding 40cm wavelength in about 2.4 cm waveguide.

كتابة محزز الحيود نوع براك على ليف بصري بشكل حرف D باستخدام ليزر الاكسايمر نوع كربتون فلورايد == Writing Of A Bragg Grating On A D-Shaped Optical Fiber Using The KrF Excimer Laser

Author name: شيماء رياض محمد علي ال طحان
Supervisor name: خليل ابراهيم حاجم
General topic: Laser Science
Specific topic: Laser Applications in Electronics and Communications Engineering
Degree: Doctorate
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:

منظومة استشعار حرارة معتمدة على محززات براغ الليفي مكتوبة بواسطة ليزر ايون الارغون 244 نانومتر == Temperature Sensing System Based On Fiber Bragg Gratings Written By 244 nm Ar+ Laser

Author name: رياض خلف احمد
Supervisor name: خليل ابراهيم حاجم
General topic: Laser Science
Specific topic: Laser Applications in Electronics and Communications Engineering
Degree: Doctorate
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:

Simulated Dissipation And Thermal Effects On Experimentally Generated Coherent And Squeezed States

Author name: اسماعيل شنان
Supervisor name: Raad Sami Fyath
General topic: Laser Science
Specific topic: Laser Applications in Electronics and Communications Engineering
Degree: Doctorate
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:

دراسة تركيب الالياف البلورية الفوتونية لليزرات ذات القدرة العالية الفعالة والاستشعار الاحيائي الكفوء ل دي اي ان == Pcfs Structure Studies For Effective High Power Laser And DNA Efficient Biosensor

Author name: رياض مواد نايف
Supervisor name: عبد الهادي مطشر الجنابي
General topic: Laser Science
Specific topic: Laser Applications in Electronics and Communications Engineering
Degree: Doctorate
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:

تاثير تغيير درجة الحرارة على خصائص الليف البصري الفوتوني البلوري المملوء بالسائل == Effect Of Temperature Variation On The Performance Of Liquid - Filled Photonic Bandgap Fiber

Author name: تحرير صفاء منصور الفلاح
Supervisor name: Abdul Hadi M. Al-Janabi
General topic: Laser Science
Specific topic: Laser Applications in Electronics and Communications Engineering
Degree: Doctorate
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages: