Date of Completion


Embargo Period



Fiber optics; Optical logic; Fiber laser

Major Advisor

Dr. Niloy.K. Dutta

Associate Advisor

Dr. Gayanath Fernando

Associate Advisor

Dr. Boris Sinkovic

Field of Study



Doctor of Philosophy

Open Access

Open Access


The next generation of fiber-optic communication system demands ultra-high speed data processing and switching components. Conventional electro-optical parts have reached their bottleneck both speed-wise and efficiency-wise. The idea of manipulating high speed data in all-optical domain is gaining more popularity. In this PhD dissertation, I showed the design and performance analysis of two kinds of ultra-fast all-optical latches, Set-Reset latch and D-flip-flop, based on two different schemes: (1) cross gain and phase modulation (XGM and XPM) in quantum dot semiconductor optical amplifiers (QD-SOA) and (2) two-photon absorption (TPA) in bulk semiconductor optical amplifiers. Design and simulation of a scheme to realize high speed all-optical encryption and decryption using key-stream generators and XOR gates based on QD-SOA are included in this dissertation. We also proposed and simulated all-optical Boolean logic functions with improved output quality using binary phase shift keyed signal based on QD-SOA. A fiber ring laser system with charcoal nano-particles as saturable absorber inside the cavity has been designed and experimentally demonstrated. This fiber ring laser system can generate optical pulse train @ 20Gb/s with improved stability and smaller pulse width comparing with the system without nano-particles in the cavity.