Related papers: Strong Coulomb effects in hole-doped Heisenberg ch…
Motivated by magnetization studies of the "telephon number compound" Sr_14Cu_24O_41 we investigate doped Heisenberg spin rings by means of complete numerical diagonalization of a Heisenberg Hamiltonian that depends parametrically on hole…
We present a full derivation of the interaction Hamiltonian for holes in silicon within the six-band envelope-function scheme, which appropriately describes the valence band close to the $\boldsymbol{\Gamma}$ point. The full structure of…
The present work studies aspects of the electronic correlation in confined H$^{-}$, He and Li$^+$ atoms in their ground states using the informational entropies. In this way, different variational wavefunctions are employed in order of…
Coulomb correlations in the optical spectra of semiconductor quantum dots are investigated using a full-diagonalization approach. The resulting multi-exciton spectra are discussed in terms of the symmetry of the involved states.…
We present a consistent theoretical description of few-particle effects in the optical spectra of semiconductor quantum dots, based on a direct-diagonalization approach. We show that, because of the strong Coulomb interaction among…
We study the effects of hole doping on the two-dimensional Heisenberg-Kondo model around the quantum critical point, where the spin liquid phase (Kondo insulator) and the magnetically ordered phase are separated via a second-order phase…
We analyze the induced interactions between localized holes in weakly-doped Heisenberg antiferromagnets due to the modification of the quantum zero point spin wave energy; i.e. the analogue of the Casimir effect. We show that this…
We review recent theoretical results for hole spins influenced by spin-orbit coupling and Coulomb interaction in two-dimensional quantum wells as well as the decoherence of single hole spins in quantum dots due to hyperfine interaction with…
The magnetic susceptibility of systems from a class of integrable models for doped spin-$S$ Heisenberg chains is calculated in the limit of vanishing magnetic field. For small concentrations $x_h$ of the mobile spin-$(S-1/2)$ charge…
The electronic structure of radially polarized excitons in structured nanorings is analyzed, with emphasis in the ground-state properties and their dependence under applied magnetic fields perpendicular to the ring plane. The electron-hole…
We present a novel and efficient real space, semiclassical model of electric polarization with general applicability to any system in which screening plays an important role. This model includes the effects of both atomic and bond…
The dynamics of an electron--hole pair induced by the time--dependent screened Coulomb interaction is discussed. In contrast to the case where the static electron--hole interaction is considered we demonstrate the occurrence of important…
We investigate the transport properties of quantum dots placed in strong magnetic field using a quantum-mechanical ' approach based on the 2D tight-binding Hamiltonian with direct Coulomb interaction and the Landauer-B\"{u}ttiker (LB)…
We consider holes confined to Ge/Si core/shell nanowires subject to strong Rashba spin-orbit interaction and screened Coulomb interaction. Such wires can, for instance, serve as host systems for Majorana bound states. Starting from a…
We use a Hartree-Fock-Koopmans approach to study spin and interaction effects in a diffusive or chaotic quantum dot. In particular, we derive the statistics of the spacings between successive Coulomb-blockade peaks. We include fluctuations…
We study theoretically a quantum dot in the quantum Hall regime that is strongly coupled to a single lead via a point contact. We find that even when the transmission through the point contact is perfect, important features of the Coulomb…
We study the homogeneous interacting hole gas in $p$-doped bulk III-V semiconductors. The structure of the valence band is modelled by Luttinger's Hamiltonian in the spherical approximation, giving rise to heavy and light hole dispersion…
Quantum spin rings represent an intriguing platform for studying unconventional magnetic order and exotic quantum phases, and they are also promising materials for emerging quantum technologies. Conventional spin systems consist of a set of…
Effects of short-range correlations on the Coulomb screening, the phonons, and the pairing interactions are examined in electron-phonon systems. First, we derive a model Hamiltonian of Coulomb interactions which includes both the long-range…
We have studied theoretically the effect of a tuneable lateral confinement on two-dimensional hole systems realised in III-V semiconductor heterostructures. Based on the 4x4 Luttinger description of the valence band, we have calculated…