Microwave signal processing based on ultrafast dynamics in quantum dot waveguides

In this paper we review theoretical work on slow and fast light effects in quantum dot (QD) semiconductor waveguides and the potential applications in microwave photonics. In particular we emphasize the unique ultrafast carrier dynamics occurring between discrete QD bound states and its influence on the dynamic gain grating and cross gain modulation in QD semiconductor optical amplifiers (SOAs). The exploitation of ultrafast carrier dynamics enables the realization of phase shifters at frequencies in the range of 100 GHz.