Related papers: Strong electron-electron interactions in Si/SiGe q…
Effect of electric field on spin splitting in SiGe quantum wells (QWs) has been studied theoretically. Microscopical calculations of valley and spin splittings are performed in the effective $sp^3d^5s^*$ tight-binding model. The splittings…
Exchange interaction has been studied for electrons in coupled quantum dots (QD's) by a configuration interaction method using confinement potentials with different profiles. The confinement potential has been parametrized by a two-centre…
We study the development of electron-electron correlations in circular quantum dots as the density is decreased. We consider a wide range of both electron number, N<=20, and electron gas parameter, r_s<18, using the diffusion quantum Monte…
Motivated by recent developments on the fabrication and control of semiconductor-based quantum dot qubits, we theoretically study a finite system of tunnel-coupled quantum dots with the electrons interacting through the long-range Coulomb…
We discuss the properties of few electrons and electron-hole pairs confined in coupled semiconductor quantum dots, with emphasis on correlation effects and the role of tunneling. We shall discuss, in particular, exact diagonalization…
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…
We demonstrate that in semiconductor quantum dots wave functions probed by imaging techniques based on local tunneling spectroscopies like STM show characteristic signatures of electron-electron Coulomb correlation. We predict that such…
The electron-hole states of semiconductor quantum dots are investigated within the framework of empirical tight-binding descriptions for Si, as an example of an indirect gap material, and InAs and CdSe as examples of typical III-V and II-VI…
We study the spin ordering of a quantum dot defined via magnetic barriers in an interacting quantum spin Hall edge. The spin-resolved density-density correlation functions are computed. We show that strong electron interactions induce a…
The electron interaction energy of two interacting electrons in a circular quantum dot (with hard wall confinement) is investigated in the framework of the semi-classical Wentzel-Kramers-Brillouin (WKB) approximation. The two electrons are…
Multi-electron semiconductor quantum dots have found wide application in qubits, where they enable readout and enhance polarizability. However, coherent control in such dots has typically been restricted to only the lowest two levels, and…
Few-electron states in carbon-nanotube quantum dots are studied by means of the configuration-interaction method. The peculiar non-interacting feature of the tunneling spectrum for two electrons, recently measured by Kuemmeth et al. [Nature…
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…
Magnetotunneling spectroscopy was employed to probe the confinement in vertical Si/Ge double-barrier resonant tunneling diodes with regularly distributed Ge quantum dots. Their current-voltage characteristics reveal a step-like behavior in…
Understanding strongly interacting electrons enables the design of materials, nanostructures and devices. Developing this understanding relies on the ability to tune and control electron-electron interactions by, e.g., confining electrons…
Artificial molecular states of double quantum dots defined in bilayer graphene are studied with the atomistic tight-binding and its low-energy continuum approximation. We indicate that the extended electron wave functions have opposite…
Research on Si quantum dot spin qubits is motivated by the long spin coherence times measured in Si, yet the orbital spectrum of Si dots is increased as a result of the valley degree of freedom. The valley degeneracy may be lifted by the…
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 states of two electrons in tunnel-coupled semiconductor quantum dots can be effectively described in terms of a two-spin Hamiltonian with an isotropic Heisenberg interaction. A similar description needs to be generalized in the case of…
Electron spins in Si/SiGe quantum wells suffer from nearly degenerate conduction band valleys, which compete with the spin degree of freedom in the formation of qubits. Despite attempts to enhance the valley energy splitting…