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المبادئ الاساسية لهوائي النانو البصري (باوتاي) The performance of Bow-tie optical nanoantenna

اسم المؤلف: غفران عبد القادر حسن
اسم المشرف: جواد عبد الكاظم حسن
الموضوع العام: علوم الليزر
السنة: 2020
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:

توليد الارقام العشوائية الحقيقة بالاعتماد على زمن وصول الفوتون True Random Number Generation Based on Photon Arrival Time

اسم المؤلف: رغد سعيد حسن
اسم المشرف: شيلان خسرو توفيق
الموضوع العام: علوم الليزر
السنة: 2016
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:

مرشح ضوئي حزمي المرور متعدد التنغيم باستخدام الالياف البلورية الفوتونية All - optical tunable bandpass filter using Photonic crystal fiber

اسم المؤلف: ميثم صبري جابر
اسم المشرف: عبد الهادي مطشر الجنابي
الموضوع العام: علوم الليزر
السنة: 2013
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:

توليد الموجه المثالية باستخدام محزز براغ الليفي Soliton Generation in Fiber BraggGrating

اسم المؤلف: ليث طارق محمد
اسم المشرف: تحرير صفاء منصور
الموضوع العام: علوم الليزر
السنة: 2017
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:

تنفيذ البوابة اكس اور بصريا بالكامل لمنظومات الاتصالات البصرية Implementation of All Optical Exclusive - OR Gate for Optical Communication Systems

اسم المؤلف: ياسمين سلمان كاظم
الموضوع العام: علوم الليزر
السنة: 2015
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: One of the most important techniques used to realize logic gates in optical networks is by all - optical signal processing.The most two important problems of electronic signal processing are high propagation loss of electronic signals and the high cost of the high speed electronics. Accordingly, these reasons led to converting to optical domain at higher frequencies (≥ 10 ????????/????) .The goal of this work is to implement all optical logic gates specifically exclusive - OR gate. Exclusive - OR gate have an important role in data encryption, parity checking, data encoding, bit pattern generation and matching, addressing, header recognition and many more applications. In this work an all - optical exclusive - OR logic function was achieved by a simulation software and implementing an experiment.In the simulation work, the exclusive - OR function was implemental by using a highly nonlinear fiber with a fiber nonlinear coefficient of 9.1 ????−1????????−1 , 0.135 km length non - degenerate with four wave mixing process and a NRZ - DPSK 10 GB/s signals.Experimentally the exclusive - OR function was implemented by using a highly non fiber with a fiber nonlinear coefficient of 10 ????−1????????−1and a 1 km length with bidirectional degenerate four wave mixing process. The optical signals that were used for the operation of the exclusive - OR function were NRZ - DPSK 40 GB/s signals. Results showed an exclusive - OR function associated with clear eye diagrams. In addition to that, exclusive - NOR function was also obtained experimentally in addition of these four maxterms (A + B, ????̅+ B, A + ???? ̅ and ????̅ +???? ̅ ).

محزز الليف البصري نوع براغ لتحسس الحرارة والضغط FIBER BRAGG GRATING FOR TEMPERATURE AND PRESSURE SENSING

اسم المؤلف: فهد محمد عبد الحسين
اسم المشرف: تحرير صفاء منصور
الموضوع العام: علوم الليزر
السنة: 2015
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Nowadays, the modern trends in optical sensing are to build simultaneous measurements sensors. In this work two schemes for simultaneous measurements sensors are presented. The first one is with dual FBGs peaks. Every FBG acts as sensing head. The first peak was used for temperature sensing and the obtained sensitivity is 10 pm/˚C and the second peak was used for temperature and pressure measurements with sensitivities 9.2 pm/˚C and 67 pm/ bar for temperature and pressure respectively.The other scheme consists of two sensing heads fabricated in the lab. The first sensing head is the Fabry - Perot interferometer which was used for load and strain measurements by controlling the size of its cavity reached to minimum value in micro scale (30). The sensitivity was increased to 4.07 nm/ N and 5.11 pm/ μɛ for load and strain respectively. This sensitivity for load is the highest that was recorded by micro cavity where previous works were reached to 1.37 nm/N. The second sensing head made by inscribing Bragg gratings inside the core of All Solid Photonic Band - Gap fiber toenhance its sensitivity that reached to 13.7 pm/˚C and 0.7 pm/μɛ for temperature and strain respectively which is more sensitive than previous works of our group in the institute that reached to 10 pm/˚C and 0.66 pm/μɛ for temperature and strain respectively. The obtained temperature sensitivity for the Bragg gratings is higher than previous work for Bragg gratings inscribed on All Solid Photonic Band - Gap Fiber where it was 12.04 pm/˚C.Strain sensitivities were almost the same.

التحقق عمليا من بروتوكول البينغ بونغ

اسم المؤلف: علاء جبار جمعة
اسم المشرف: شيلان خسرو توفيق
الموضوع العام: علوم الليزر
السنة: 2015
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Quantum cryptography uses basic laws of quantum physics to guarantee secure key exchange. The key can be used with unprecedented confidence in any classic cryptographic protocol, where it increases the security to the maximum achievable value. The goal of this work is to encrypt the message directly without need to generate the secure key by using the modified Ping - Pong Protocol. A quantum cryptography system based on Modified Ping - Pong Protocol was designed and implemented for the first time. A polarization - entangled photons were generated by a source using PPKTP crystal inside a polarization Sagnac interferometer at telecom wavelength 1550 nm and a fiber length of 15 Km. In this experiment, Bob prepares entangled photons, sends one photon to Alice by optical fiber to perform one out of four operators according to the message. The modulated photon is sent back to Bob. Then the Bell’s state measurement is applied to extract the message according to the Alice’s coding. The HOM - dip of the two - photon interference was verified to guarantee perfect system performance. The final results showed the switching between the Bell’s states, |????+⟩ and |????−⟩ as the phase of the phase modulator was changed by Alice achieving an acceptable coincidence count of about 625 counts per 30s. These results proves also two photon interference needed to test Bell’s enquality.

الليف البلوري الفوتوني لاستشعار المجال المغناطيسي Photonic crystal fiber magnetic sensor

اسم المؤلف: احمد عدنان محمد
اسم المشرف: عبد الهادي مطشر الجنابي
الموضوع العام: علوم الليزر
السنة: 2015
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Photonic crystal fiber (PCF) is widely used for sensing applications. In this work, magnetic sensor based on solid core - PCFs for sensing magnetic field was presented. The general structure of the sensor applied is by splicing short lengths of PCF (LMA - 10) with conventional single mode fiber (SMF - 28) in one side and using free space connector from other side. A laser diode with different wavelengths (850, 1060 and 1300 nm) has been used as a light source, where a high sensitive optical spectrum analyzer (OSA) was used to monitor and record the transmitted/reflected spectra.The present work demonstrates the results of the infiltration of the air holes for the PCFs by fluids instead of air. For magnetic sensing, the magnetic fluids being used were prepared and standard ????????3????4 to infiltrate the air holes for the solid core PCF (LMA - 10) which leads to change in the effective refractive index of the PCF, which in turn affects the transmission of the laser inside the PCF due to the value of the refractive indices of the magnetic fluids. The experiments show that the power of transmissionspectrum of the laser had decreased after infiltration without any change in central wavelength of the laser diode the reason is that after PCF air holes infiltration, the effective refractive index has been changed but still within total internal reflectionwhich leads to loss of some fundamental modes, in turn leads to decrease the power of transmission spectrum. The decrease of the transmitted power in the case of standard has been higher than it in the case of prepared ????????3????4 because of the differencein concentration between standard and prepared magnetic fluids. The power of transmission spectrum after PCF infiltration will be increased with increasing magnetic field. Higher sensitivity has been obtained that reached 5.809 nW/mT which consideredhigher than previously published works on PCF magnetic sensors.

تصميم وتنفيذ دائرة تشغيل اخماد نشط لكشف فوتون مفرد Design And Implementation Ac Active Quenching Driving Circuit For Signle Photon Detection

اسم المؤلف: عمار خلف عبد الحسين
اسم المشرف: خليل ابراهيم حاجم
الموضوع العام: علوم الليزر
السنة: 2012
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:

Quantum Bit Error Rate Performance Test For A Quantum Cryptography System

اسم المؤلف: احمد اسماعيل خليل
اسم المشرف: Shelan Khasro Tawfeeq
الموضوع العام: علوم الليزر
السنة: 2009
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:

منظومة توزيع المفتاح الكمي ذو الحالة الزائفة Decoy - State Quantum Key Distribution System

اسم المؤلف: سرى عادل عباس
اسم المشرف: Shalane Khasro Tawfeeq
الموضوع العام: علوم الليزر
السنة: 2011
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:

الحساب التقليدي لخوارزميات شور وكروفر ودووتج الكمية Classical Computation Of Shor’s, Grover’s And Deutsch’s Quantum Algorithms

اسم المؤلف: امجد يوسف صاحب
اسم المشرف: خليل ابراهيم حاجم
الموضوع العام: علوم الليزر
السنة: 2013
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى: