QDot and GaInNAs/GaAs Broadband Semiconductor Optical Amplifiers for Simultaneous Multiwavelength Amplification

The need for simultaneous multi-channel transmission in optical communication systems has led to a requirement of semiconductor optical amplifiers (SOAs) with flat gain over a broad range of wavelengths and minimum channel interspacing for the independent and simultaneous amplification of several different laser sources. In addition for ultra-high speed communication with femto-second pulses, composed of a spectrum of wavelengths, simultaneous multi-wavelength amplification is required. The goal of this paper is the modelling, fabrication and characterization of SOAs made from GaInNAs/GaAs quantum-well edge emitting lasers and InAs/GaAs QDot edge-emitting lasers. Both QDots and GaInNAs/GaAs quantum wells (QWs) exhibit broad gain for a range of temperatures and current as measured experimentally.