Temperature studies on a single InAs/InP QD layer laser emitting at 1.55 µm
Résumé
This paper presents the temperature dependent characteristics of a semiconductor laser with a single quantum dot (QD) layer on InP(311)B substrate. The laser emits in the optical telecommunication wavelength band near 1.55 µm and shows a threshold current density of 6 A/cm2 at low temperature, attesting excellent material quality. Laser spectra obtained under electrical injection for different temperatures show a drastic influence on their shape. A large spectral broadening is observed at low temperature, while it dramatically narrows close to room temperature. This is due to homogeneous broadening of each QD with increasing temperature, favouring a collective emission of the QDs and homogeneous gain.