相关论文: Vertically coupled quantum dots in the local spin-…
Controlling electron spins strongly coupled to magnetic and nuclear spins in solid state systems is an important challenege in the field of spintronics and quantum computation. We show here that electron droplets with no net spin in…
Quantum dots are fabricated in a Ga[Al]As-heterostructure by local oxidation with an atomic force microscope. This technique, in combination with top gate voltages, allows us to generate steep walls at the confining edges and small lateral…
We study a small spin-degenerate quantum dot with even number of electrons, weakly connected by point contacts to the metallic electrodes, and subject to an external magnetic field. If the Zeeman energy B is equal to the single-particle…
The electronic structure of an infinite 1D array of vertically coupled InAs/GaAs strained quantum dots is calculated using an eight-band strain-dependent k-dot-p Hamiltonian. The coupled dots form a unique quantum wire structure in which…
We review our investigation of the spin dynamics for two electrons confined to a double quantum dot under the influence of the hyperfine interaction between the electron spins and the surrounding nuclei. Further we propose a scheme to…
We study theoretically the electron states in a system of two vertically stacked quantum dots. We investigate the influence of the geometrical symmetry breaking (caused by the displacement as well as the ellipticity of the dots) on the…
We study the spin filling of a semiconductor quantum dot using excited-state spectroscopy in a strong magnetic field. The field is oriented in the plane of the two-dimensional electron gas in which the dot is electrostatically defined. By…
The current-voltage characteristic of a one dimensional quantum dot connected via tunnel barriers to interacting leads is calculated in the region of sequential tunneling. The spin of the electrons is taken into account. Non-Fermi liquid…
We present a microscopic theory of the optical properties of self-assembled quantum dots doped with a single magnetic manganese (Mn) impurity and containing a controlled number of electrons. The single-particle electron and heavy-hole…
We address the electronic properties of quantum dots in the two-dimensional $\alpha-\mathcal{T}_3$ lattice when subjected to a perpendicular magnetic field. Implementing an infinite mass boundary condition, we first solve the eigenvalue…
We have investigated edge modes of different multipolarity sustained by quantum dots submitted to external magnetic fields. We present a microscopic description based on a variational solution of the equation of motion for any axially…
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 have investigated the far-infrared dipole modes of a quantum antidot submitted to a perpendicularly applied magnetic field B. The ground state of the antidot is described within local spin-density functional theory, and the spectrum…
Low-lying energy levels of two interacting electrons confined in a two-dimensional parabolic quantum dot in the presence of an external magnetic field have been revised within the frame of a novel model. The present formalism, which gives…
The charge density and pair correlation function of three interacting electrons confined within a two-dimensional disc-like hard wall quantum dot are calculated by full numerical diagonalization of the Hamiltonian. The formation of a…
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…
It is shown that the low-energy spin states of double quantum dots (DQD) with even electron occupation number $N$ possess the symmetry SO(4) similar to that of a rigid rotator familiar in quantum mechanics (rotational spectra of H$_2$…
We calculate the orbital magnetization of single and double quantum dots coupled both by Coulomb interaction and by electron tunneling. The electronic states of the quantum dots are calculated in a tight-binding model and the magnetization…
Using far-infrared spectroscopy, we investigate the excitations of self-organized InAs quantum dots as a function of the electron number per dot, 1<n<6, which is monitored in situ by capacitance spectroscopy. Whereas the well-known two-mode…
We investigated the peculiarities of non-equilibrium charge states and spin configurations in the system of two strongly coupled quantum dots (QDs) weakly connected to the electrodes in the presence of Coulomb correlations. We analyzed the…