Research On Characterristics Of Optical Switch Based On Asymmetric Demultiplexing Structure Using Semiconductor Optical Amplifiers

With the advent of the global information era, the Internet data traffic are growingrapidly, which forces people to use the all optical communications network to replacethe existing telecommunications network to achieve huge communication bandwidth,high transmission rate and flexibility switching. In the all-optical network wherehigh-speed transmission and all-optical switching are essential, optical switches play animportant role in the wavelength selection, routing, optical cross-connecting,self-healing protection. Due to the advantages of semiconductor optical amplifiers(SOAs) such as large nonlinear coefficiency, small volume, and easily being integrated,we propose and investigate a new kind of SOA-based optical switch with TOAD(terahertz optical asymmetric demultiplexer) configuration. The paper mainly includesthe following three parts.A theoretical analysis of the semiconductor optical amplifier is presented. Itincludes the nonlinearity, the basic equations of the field transmission, the carrier rateequation and the gain characteristics of SOA. The SOA-based cross-gain modulation issimulated by OptiSystem7, and the cross-gain modulation experiments is conducted.These results provide a solid basis for the investigation on optical switches.A new SOA-based all-optical switch is proposed and its working mechanism istheoretically analyzed. In the simulation using MATLAB, the impact of the controlpulse power, delay time, the bias current on the all-optical switch is discussed, which ishelpful for the next experiments.An experimental study on the proposed optical switch structure is carried out. Theexperiments have realized the optical switch with an adjustable width of the switchingwindow at2.5GHz. The research of the experiments have included the impact of biascurrent of SOA, the delay time induced by the optical delay line’s length, the controllingoptical signal power, continuous optical power, continuous polarization states of lightexperiment on the switching window. In the end, we give a detailed analysis on theexperimental results.