Controlling Photon Echo in a Quantum-Dot Semiconductor Optical Amplifier Using Shaped Excitation

Abstract

Two-pulse photon-echo-based quantum-memory applications require a precise control over the echo strength and appearance time. We describe a numerical investigation of observation and control of photon echo in a room-temperature InAs/InP-based quantum-dot (QD) semiconductor optical amplifier (SOA). We address an important case where the spectral excitation is narrower than the inhomogeneous broadening of the SOA. It is revealed that, in such a QD SOA, the amplitude of the echo pulse depends not only on the excitation-to-rephasing pulse temporal separation but also on the interference among the rephrasing pulse and the echo pulses generated during the propagation along the amplifier. More importantly, the appearance time and amplitude of the echo pulse can be precisely controlled by shaping the first (excitation) pulse. We also assert that deviations in the echo pulse stemming from the SOA gain inhomogeneity can be compensated for so as to be utilized in quantum coherent information processing. © 2017 American Physical Society.