High Speed All Optical Logic Gates Based on InAs/GaAs Quantum-Dot Semiconductor Optical Amplifiers

摘要

A scheme to realize fiber-based all-optical Boolean logic functions including XOR, AND, OR and NOT based on a semiconductor optical amplifier with a closely stacked Stranski-Krastanow InAs/GaAs quantum dot layers is proposed. Rate equations is given to describe the population dynamics of the carrier in the device, as well as the nonlinear dynamics including carrier heating and spectral hole-burning. The model is used to simulated the cross gain and cross phase modulation in the device that are related to the logic processes. Results show with QD excited state serving as a carrier reservoir, this type of QD device is suitable for high speed operations with ultra fast carrier and phase relaxation. All optical logic operation can be carried out at up to 250 Gb/s.