Related papers: Electronic structure of few-electron concentric do…
Few-electron eigenstates confined in coupled concentric double quantum rings are studied by the exact diagonalization technique. We show that the magnetic field suppresses the tunnel coupling between the rings localizing the single-electron…
Within local-spin-density functional theory, we have investigated the `dissociation' of few-electron circular vertical semiconductor double quantum ring artificial molecules at zero magnetic field as a function of inter-ring distance. In a…
The ground states of few electrons confined in two vertically coupled quantum rings in the presence of an external magnetic field are studied systematically within the current spin-density functional theory. Electron-electron interactions…
We study the artificial molecular states formed in laterally coupled double semiconductor nanorings by systems containing one, two and three electrons. An interplay of the interring tunneling and the electron-electron interaction is…
The electronic properties of semiconductor, vertical, double quantum dot systems with few electrons are investigated by means of analytic, configuration-interaction, and mean-field methods. The combined effect of a high magnetic field,…
We study the effects of electron-electron interactions in a circular few-electron vertical quantum dot in such a strong magnetic field that the filling factor $\nu\le 1$. We measure excitation spectra and find ground state transitions…
The spectral properties of up to four interacting electrons confined within a quasi one--dimensional system of finite length are determined by numerical diagonalization including the spin degree of freedom. The ground state energy is…
Many-electron systems confined to a quasi-1D geometry by a cylindrical distribution of positive charge have been investigated by density functional computations in the unrestricted local spin density approximation. Our investigations have…
Motivated by recent experiments [A. Lorke {\em et al.}, Phys. Rev. Lett.\ {\bf 84}, 2223 (2000)] an analysis of the ground state and far-infrared absorption of two electrons confined in a quantum ring is presented. The height of the…
Few-electron systems confined in a quantum dot laterally coupled to a surrounding quantum ring in the presence of an external magnetic field are studied by exact diagonalization. The distribution of electrons between the dot and the ring is…
We investigate the electron localization in double concentric quantum rings (DCQRs) when a perpendicular magnetic field is applied. In weakly coupled DCQRs, the situation can occur when the single electron energy levels associated with…
We present an analytically solvable model of $P$ colinear, two-dimensional quantum dots, each containing two electrons. Inter-dot coupling via the electron-electron interaction gives rise to sets of entangled ground states. These ground…
In order to understand the orbital and spin magnetization of a confined electronic system we analyze these ground state properties in the transition from a quantum dot to a quantum ring of finite thickness. The Coulomb interaction between…
We study a system in which electrons in a two-dimensional electron gas are confined by a nonhomogeneous nuclear spin polarization. The system consists of a heterostructure that has non-zero nuclei spins. We show that in this system…
We calculate that the electron states of strained self-assembled Ge/Si quantum dots provide a convenient two-state system for electrical control. An electronic state localized at the apex of the quantum dot is nearly degenerate with a state…
We have investigated the dipole charge- and spin-density response of few-electron two-dimensional concentric nanorings as a function of the intensity of a perpendicularly applied magnetic field. We show that the dipole response displays…
The conduction band electron states of laterally-coupled semiconductor quantum rings are studied within the frame of the effective mass envelope function theory. We consider the effect of axial and in-plane magnetic fields for several…
Making use of a droplet-epitaxial technique, we realize nanometer-sized quantum ring complexes, consisting of a well-defined inner ring and an outer ring. Electronic structure inherent in the unique quantum system is analyzed using a…
We have computed the low energy quantum states and low frequency dynamical susceptibility of complex quantum spin systems in the limit of strong interactions, obtaining exact results for system sizes enormously larger than accessible…
We theoretically investigate correlated electron-hole states in vertically coupled quantum dots. Employing a prototypical double-dot confinement and a configuration-interaction description for the electron-hole states, it is shown that the…