Discussion of Ph.D. Student Nidaa Lafta at laser and Optoelectronics department on Tuesday 15-7-2025 about her thesis 

“Design and Construction Add Drop Multiplexer Based on Serial and Parallel Photonic Crystal Fiber”

abstract:

This dissertation focuses on the design and fabrication of Long-Period Fiber Bragg Gratings (LPFBGs) in various optical fibers for use in optical filtering and communication systems. A point-by-point (PbP) technique using a CO₂ laser was employed to inscribe the gratings without the need for pretreatment or costly equipment. LPFBGs were fabricated in three fiber types: Single-Mode Fiber (SMF), Hollow-Core Photonic Crystal Fiber (HC-PCF), and No-Core Fiber (NCF), with various laser power settings. The spectral characteristics of the gratings were analyzed, showing optimal performance at 1.7 W for SMF, 1 W for HC-PCF, and 3 W for NCF. After fabrication, the tunability of the gratings was evaluated using sucrose solutions with different refractive indices. The experimental results demonstrated strong spectral responses to refractive index variations, confirming the gratings’ effectiveness in optical sensing and communication applications.

The degree of discussion is excellent