Dynamic amplitude-phase coupling in quantum-dot lasers

Abstract

The well-known α-factor is a convenient measure to describe the magnitude of the amplitude-phase coupling of semiconductor lasers. But is the α-factor really a parameter? First-principle simulations of InGaAs quantum-dot lasers and amplifiers show that in spatially extended quantum-dot laser structures, the amplitude phase coupling is far from being a constant. Our computation of the α-factor demonstrates the same large and excitation-dependent variation and scatter as corresponding to experimentally determined values. Our results therefore provide a key to the interpretation and give a measure of applicability of the α-factor for the classification of quantum-dot lasers.