Carrier escape from ground state and non-zero resonance frequency at low bias powers for semiconductor quantum-dot lasers

Cheng Wang (1) , Frederic Grillot (1) , Jacky Even (1)

1 FOTON - Fonctions Optiques pour les Technologies de l'informatiON

The three-dimensional confinement of electrons and holes in the semiconductor quantum dot (QD) structure profoundly changes its density of states compared to the bulk semiconductor or the thin-film quantum well (QW) structure. The aim of this paper is to theoretically investigate the microwave properties of InAs/InP(311B) QD lasers. A new expression of the modulation transfer function is derived for the analysis of QD laser modulation properties based on a set of four rate equations. Analytical calculations point out that carrier escape from ground state (GS) to excited state (ES) induces a non-zero resonance frequency at low bias powers. Calculations also show that the carrier escape leads to a larger damping factor offset as compared to conventional QW lasers. These results are of prime importance for a better understanding of the carrier dynamics in QD lasers as well as for further optimization of low cost sources for optical telecommunications.

Domaines: Optique / photonique

Cheng Wang, Frederic Grillot, Jacky Even. Carrier escape from ground state and non-zero resonance frequency at low bias powers for semiconductor quantum-dot lasers. SPIE Photonics Europe, Apr 2012, brussels, Belgium. ⟨hal-00805233⟩