Performance and physics of quantum-dot lasers with self-assembledcolumnar-shaped and 1.3-Μm emitting InGaAs quantum dots

摘要

This paper reports recent developments of our self-assemblednInGaAs quantum-dot (QD) lasers and their unique physical properties. Wenachieved a low-threshold current of 5.4 mA at room temperature with ournoriginally designed columnar-shaped QD's, and also, room-temperaturen1.3-Μm continuous-wave (CW) lasing with self-assembled dots grown atna decreased growth rate and covered by a strained InGaAs layer. Wendiscuss influence of homogeneous broadening of single-dot optical gainnon lasing spectra, influence of nonradiative carrier recombination onntemperature characteristics of threshold currents, a model for thenorigin of the homogeneous broadening, a finding of random telegraphnsignals, and suppression of temperature sensitivity of interbandnemission energy by covering dots with a strained InGaAs layer