InAs self-assembled quantum-dot lasers grown on (100) InP

Abstract

Five stacked layers of InAs quantum dots (QDs) embedded in quaternary InGaAsP are grown on (100) InP substrate to form a laser diode. The QD ensemble has a density of 1.5×1010 cm−2 and emits light at ∼1.6 μm at 77 K. Lasing wavelength and threshold current density can be shifted by changing the cavity length of the laser diode and the latter reaches a value as low as 49 A/cm2 at 77 K for a gate size of 2000 μm×150 μm. Temperature dependence of the threshold current is observed implying the presence of thermionic emission increasing with temperature.