A Multi-Section Quantum-Dot Semiconductor Optical Amplifier for Ultrabroad-Band Gain-Flattened Low-Noise Amplification

We propose an ultrabroad-band 1R regenerator utilizing a multi-section quantum-dot semiconductor optical amplifier. Due to the reduced electron states, quantum dot is beneficial in broadening the gain spectrum and lowering the noise figure. Combining this with a multi-section structure drastically improves the gain equality among the different bound states, leading to an increase in the maximum output power and an improvement of the noise figure.