Stephen Hegarty

Tyndall National Institute, Cork, Ireland

Quantum-dot lasers subject to external optical perturbation

 

Semiconductor quantum-dot lasers have long been proposed as sources resistant to destabilisation under the influence of external optical feedback, and in the case of InAs quantum-dots grown on GaAs substrates, this has indeed been shown to be true, at least when operating at the 1.3 micron telecommunications window. In this talk I will discuss two extensions to this experiment, where the perturbing external mirror is replaced firstly by an isolated master laser, and then by a non-isolated quantum-dot laser, giving a mutually coupled configuration. Both configurations give wide regions of stability in parameter space, as well as a variety of dynamical states such as excitable pulsing and multi-stability. I will present finally current attempts to understand these phenomena through rate-equation modelling.