Influence of carrier capture-escape processes on dynamical behaviour and characteristics of quantum dot laser

摘要

The space carrier confinements in all three directions at very small size (linear size is below or equal to the exciton Bohr radius) reduce to the discrete power spectrum of carriers inside the quantum dot (QD). This results in a significant improvement in the QD laser structure properties. Also if the distance between the energy states considerably exceeds the value of the thermal energy, "fizzing" carriers in the power window about kT can be avoided. Theoretical and experimental research into QD lasers has been conducted over many papers and most attention has been given to the amplification phenomenon in QDs and a definition of the threshold currents. The processes of carrier capture and escape play an essential role in the dynamics of quantum well lasers. In QD lasers these processes have a large influence too. In particular, the escape processes can cause the spatial hole burning effect. In this work we present a three-level transmission-line model of the QD laser. Using this model we study numerically the influence of carrier capture-escape processes on optical response, modulations and current watt (CW) characteristics from QD lasers.