Understanding Electrical and Optical Modulation Properties of Semiconductor Quantum-Dot Lasers in Terms of Their Turn-On Dynamics

Abstract

The optical modulation properties of a semiconductor quantum-dot laser, as observed under optical injection, depend crucially on the internal carrier-carrier scattering processes within the device. In this paper we show that in order to predict the modulation properties of the laser it is most important to know the dynamics observed during the laser turn-on. In contrast to quantum-well lasers the turn-on damping of quantum-dot devices depends strongly nonlinear on the carrier-scattering lifetimes. Thus, different QD laser devices with internally scattering processes taking place on completely different time scales, can yield equal injection dynamics due to a qualitatively similar turn-on dynamics.