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Register a new userHigh Nonlinear Photonic Crystal Fibers (PCF) Design with Very Low Confinement Loss
تصميم ألياف بلورية فوتونية عالية اللاخطية ذات خسارة حصر منخفضة جدا
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الألياف البلورية الفوتونية هي نوع جديد من الألياف البصرية, مصنوعة من مادة واحدة و تحتوي ثقوباً هوائية في الغلاف, تجري في هذا البحث دراسة و مقارنة الخصائص البصرية, مثل المساحة الفعالة و خسارة الحصر و اللاخطية, بين ثلاث بنى مختلفة لليف البلوري الفوتوني (البنية السداسية و البنية الثمانية و البنية العشارية) و ببارامترات بنيوية مختلفة (عدد حلقات الثقوب الهوائية و قطر الثقب الهوائي و ثابت الشبكية)، و ذلك بهدف استخدام هذا الليف في مضخمات رامان البصرية, تمت نمذجة هذه البنى بالاستعانة ببرنامج (COMSOL MULTIPHYSICS), الذي يعتمد في الحل على طريقة العناصر المنتهية. تبين من نتائج المحاكاة الرقمية أن الليف البلوري الفوتوني ذي البنية العشارية يؤمن اخفض خسارة للحصر و اصغر مساحة فعالة بالإضافة إلى أعلى معامل لاخطية و ذلك بالمقارنة مع البنيتين الأخريين، و هذا يؤهله لأغلب تطبيقات شبكات الاتصالات البصرية بعيدة المسافة .
A Photonic Crystal Fiber (PCF) is a special class of optical fibers which is made of a single material and having air holes in the cladding. This paper studies and compares the optical characteristics such as effective area, confinement loss and nonlinearity, among three different PCF's structures: Hexagonal PCF (HPCF), Octagonal PCF (O-PCF) and Decagonal PCF (D-PCF) with varied structural parameters (number of the air-holes rings, the air-hole's diameter, and the lattice constant), and the target is to use the fiber in a Raman amplifier. Proposed structures are simulated by using COMSOL MULTIPHYSICS which depends on Finite Element Method (FEM). The numerically simulated results shows that Decagonal PCF (D-PCF) offers lower confinement loss, lower effective area, and larger value of nonlinearity than the other two structures. It is seen that Decagonal PCF(D-PCF) is suitable for long transmission fiber applications.
References used
ZOLLA,F;RENVERSEZ,G; NICOLET,A. Foundations of Photonic Crystal Fibers. Imperial College Press, Singapore & London,2005,376
AGRAWAL, GOVIND,P. Raman Amplification in Fiber Optical Communication Systems. Elsevier Academic Press, USA, 2005, 383
SAITOH,K; TSUCHIDA,Y; KOSHIBA,M. Endlessly single-mode holey fibers: the influence of core design. Optical Society of America Japan,2005
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