Search

We present experimental evidence that at room temperature the main coupling mechanism between an n-type δ-doping region and an adjacent plane of dots is energy-conserving electron-electron scattering, in which a hot electron in the δ-doping region transfers energy to a deeply confined electron in that region and relaxes to the quantum dot. We demonstrate that at room temperature the increased capture cross section due to electron-electron scattering considerably enhances the injection into the quantum dots with a certain size and thus reduces the phonon bottleneck in quantum dot assemblies for the quantum dots that interact with the δ-doping region. We identify different temperature-dependent injection schemes by comparing the photoluminescence of dilute and dense assemblies with the corresponding photoluminescence of similar structures including n-type δ-doping regions adjacent to the dots’ plane. [ABSTRACT FROM AUTHOR]

We describe a theoretical model for the linear optical gain properties of a quantum wire assembly and compare it to the well known case of a quantum dot assembly. We also present a technique to analyze the gain of an optical amplifier using bias dependent room temperature amplified spontaneous emission spectra. Employing this procedure in conjunction with the theoretical gain model, we demonstrate that InAs/InP quantum dash structures have quantum-wire-like characteristics. The procedure was used to extract the net gain coefficient, the differential gain, and the relative current component contributing to radiative recombination. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]