Long-lived dark exciton states are formed in self-assembled quantum dots due to the combination of the angular momentum of electrons and holes. The lifetime of dark excitons are determined by spin-flip processes that transfer dark excitons into radiative bright excitons. We employ time-resolved spontaneous emission measurements in a modified local density of optical states to unambiguously reco...

In this paper, we investigate variation of the wavelength, intensity and polarization of the self-assembled InAs/GaAs quantum dots emission by microphotoluminescence spectroscopy at the liquid helium temperature. The microcavity wafer sample is grown by molecular beam epitaxy (MBE) and chemically etched into the micropillar structure (with elliptical cross section - long and short axis 2µm×1.5µ...

A three-dimensional (3-D) simulator is presented which uses a linear-response approach to simulate the conductance of semiconductor single-electron transistors at the solid-state level. The many-particle groundstate of the quantum dot, weakly connected to the drain and the source reservoir, is evaluated in a self-consistent manner including quantum-mechanical many-body interactions. A transfer-...

We report the effect of dissimilar anion anneals on the properties of layered quantum dot structures exhibiting vertical self-organization. Such anneals may provide an additional means of controlling dot properties, such as composition, size, and position. In addition, the modification of surface strain is critical to the subsequent nucleation of dots after the initial seed layer. Anion exchang...

We briefly review the physics of gate operations between quantum dot spin-qubits and analyze the dynamics of quantum entanglement in such processes. The indistinguishable character of the electrons whose spins realize the qubits gives rise to further entanglement-like quantum correlations that go beyond simple antisymmetrization effects. We also summarize further recent results concerning this ...

Semiconductor crystals smaller than about 10 nm, known as quantum dots, have properties that differ from large samples, including a band gap that becomes larger for smaller particles. These properties create several applications for quantum dots. In this paper new shapes of quantum dot arrays are used to enhance the photo physical properties of gold nano-particles. This paper presents a study o...

G. Huyet; 1, D. O’Brien1, S. P. Hegarty1, J. G. McInerney1, A. V. Uskov2, D. Bimberg3, C. Ribbat3, V. M. Ustinov4, A. E. Zhukov4, S. S. Mikhrin4, A. R. Kovsh4, J. K. White5, K. Hinzer5, and A. J. SpringThorpe6 1 Physics Department, National University of Ireland, University College Cork, Cork, Ireland 2 NMRC, National University of Ireland, University College Cork, Lee Malting, Cork, Ireland 3 ...

Different approaches to the design of a genuinely temperature-insensitive quantum dot (QD) laser are proposed. Suppression of the parasitic recombination outside the QDs, which is the dominant source of the temperature dependence of the threshold current in the conventional design of a QD laser, is accomplished either by tunneling injection of carriers into the QDs or by band-gap engineering. E...