相关论文: Discontinuities in the level density of small quan…
The longitudinal dipole response of a quantum dot has been calculated in the far-infrared regime using local spin density functional theory. We have studied the coupling between the collective spin and density modes as a function of the…
We analyse the ground state of spinless fermions on a lattice in a weakly disordered potential, interacting via a nearest neighbour interaction, by applying the self-consistent Hartree-Fock approximation. We find that charge density…
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 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 model of Composite Fermions for describing interacting electrons in two dimensions in the presence of a magnetic field is described. In this model, charged Fermions are combined with an even number of magnetic flux quanta in such a way…
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…
For a fermion gas with equally spaced energy levels that is subjected to a magnetic field, the particle density is calculated. The derivation is based on the path integral approach for identical particles, in combination with the inversion…
In two-dimensional electron systems confined to wide AlAs quantum wells, composite fermions around the filling factor $\nu$ = 3/2 are fully spin polarized but possess a valley degree of freedom. Here we measure the energy needed to…
We demonstrate the formation of composite fermions in two-dimensional quantum dots under high magnetic fields. The composite fermion interpretation provides a simple way to understand several qualitative and quantitative features of the…
Exact diagonalization results are reported for the lowest rotational band of N=6 electrons in strong magnetic fields in the range of high angular momenta 70 <= L <= 140 (covering the corresponding range of fractional filling factors 1/5 >=…
Properly regularized second-order degenerate perturbation theory is applied to compute the contribution of higher Landau levels to the low-energy spectrum of interacting electrons in a disk-shaped quantum dot. At ``filling factor'' near…
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…
Excitation modes in the range $2/5 \geq \nu \geq 1/3$ of the fractional quantum Hall regime are observed by resonant inelastic light scattering. Spectra of spin reversed excitations suggest a structure of lowest spin-split Landau levels of…
We have investigated low energy excitations of a disk of electrons in half-filled Landau level using trail wave function and small-size exact diagonalization approaches. We have constructed a set of many-body basis states that describe…
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…
There is controversy as to whether a one-dimensional (1D) electron gas can spin polarise in the absence of a magnetic field. Together with a simple model, we present conductance measurements on ultra low-disorder quantum wires supportive of…
Using different techniques, and Fermi-liquid relationships, we calculate the variation with applied magnetic field (up to second order) of the zero-temperature equilibrium conductance through a quantum dot described by the impurity Anderson…
In wide GaAs quantum wells where two electric subbands are occupied we apply a parallel magnetic field or increase the electron density to cause a crossing of the two $N=0$ Landau levels of these subbands and with opposite spins. Near the…
We study the applicability of composite fermion theory to electrons in two-dimensional parabolically-confined quantum dots in a strong perpendicular magnetic field in the limit of low Zeeman energy. The non-interacting composite fermion…
The electronic states of lateral many electron quantum dots in high magnetic fields are analyzed in terms of energy and spin. In a regime with two Landau levels in the dot, several Coulomb blockade peaks are measured. A zig-zag pattern is…