Related papers: Magnetism in one-dimensional quantum dot arrays
The total energy of a quasi-one-dimensional electron system is calculated using density functional theory. It is shown that spontaneous ferromagnetic state in quantum wire occurs at low one-dimensional electron density. The critical…
Magnetic properties of two and three-dimensional clusters of quantum dots are studied with exact diagonalization of a generalized Hubbard model. We study the weak coupling limit, where the electrons interact only within a quantum dot and…
The density functional theory is used to study the electronic structure of a quantum wire in a magnetic field. The Kohn-Sham equations are solved numerically for different values of electron densities and filling factors. The critical…
We apply quantum electrodynamical density functional theory to obtain the electronic density, the spin polarization, as well as the orbital and the spin magnetization of square periodic arrays of quantum dots or antidots subjected to the…
The magnetization of quantum dots is discussed in terms of a relatively simple but exactly solvable model Hamiltonian. The model predicts oscillations in spin polarization as a function of dot radius for a fixed electron density. These…
The separate and combined influences of the spin-orbit and electron-electron interactions on the electron magnetization in quantum rings have been studied theoretically on the basis of the spin-density-functional theory and the Kohn-Sham…
We use density-functional methods to study the effects of an external magnetic field on two-dimensional quantum dots with a rectangular hard-wall confining potential. The increasing magnetic field leads to spin polarization and formation of…
The spin structure in a magnetic dot, which is an example of a quantum few-body system, is studied as a function of exchange coupling strength and dot size with in the semiclassical approximation on a discrete lattice. As the exchange…
We address low-density two-dimensional circular quantum dots with spin-restricted Kohn-Sham density functional theory. By using an exchange-correlation functional that encodes the effects of the strongly-correlated regime (and that becomes…
Similar to atoms and nuclei, semiconductor quantum dots exhibit formation of shells. Predictions of magnetic behavior of the dots are often based on the shell occupancies. Thus, closed-shell quantum dots are assumed to be inherently…
The density functional theory is used to study the electronic structure of a quantum wire in a magnetic field. In a GaAs quantum wire, a critical density has been found, below which the electron density has a strong spatial inhomogeneity.…
We calculate the magnetization of quantum dots deviating from circular symmetry for noninteracting electrons or electrons interacting according to the Hartree approximation. For few electrons the magnetization is found to depend on their…
There has been considerable debate on the onset of exotic spin phenomena in quantum wires due to enhanced many-body effects caused by the one-dimensional (1D) alignment of charge carriers. We explain various observed spin effects, such as a…
We study the ground state properties of rectangular quantum dots by using the spin-density-functional theory and quantum Monte Carlo methods. The dot geometry is determined by an infinite hard-wall potential to enable comparison to…
Linear and nonlinear transport of quantum wires is investigated at a magnetic field where spin-split one-dimensional (1D) subbands are equidistant in energy. In this seldom-studied regime, experiments are consistent with a density-dependent…
Quantum magnetism describes the properties of many materials such as transition metal oxides and cuprate superconductors. One of its elementary processes is the propagation of spin excitations. Here we study the quantum dynamics of a…
An existence of predominant symmetrical spin configuration (spin polarised phase) and "diluted" density of states (pseudo-gap) in a layer under the Fermi level in a quantum wire is predicted. The condition of cross-over from non-polarised…
Quantum dots in magnetic fields are studied within the current spin density functional formalism avoiding any spatial symmetry restrictions of the solutions. We find that the maximum density droplet reconstructs into states with broken…
We discuss an exactly solvable model Hamiltonian for describing the interacting electron gas in a quantum dot. Results for a spherical square well confining potential are presented. The ground state is found to exhibit striking oscillations…
A two-dimensional array of quantum dots in a magnetic field is considered. The electrons in the quantum dots are described as unitary random matrix ensembles. The strength of the magnetic field is such that there is half a flux quantum per…