Pulse distortion in a quantum dot optical amplifier

Summary form only given. Semiconductor optical amplifiers are essential elements in all-optical signal processing due to their high gain and high bandwidth. With the increasing bit rate demand in OTDM systems, subpicosecond pulse dynamics becomes important. The superiority of optical amplifiers based on quantum dot (QD) gain materials with respect to temperature stability and low drive current makes these devices especially interesting to study. Experimental results on pulse propagation in an electrically-pumped QD amplifier using a novel phase-sensitive pulse characterization technique are presented. The QD device is a P-I-N structure grown by MOCVD. The active region consists of three layers of binary/ternary InAs/InGaAs QDs separated by 21-nm-thick GaAs barriers, in the center of a 120-nm-thick GaAs layer.