Related papers: Multipole excitations in quantum dots
The far-infrared absorption of triangular and square two-dimensional quantum dots is studied by means of time simulations of the density oscillations within the time-dependent local-spin-density approximation. The absorption is spatially…
Collective excitations of many-body electron systems can carry internal structure, tied to the quantum geometry of the Hilbert space in which they are embedded. This has been shown explicitly for particle-hole-like excitations, which carry…
We provide a microscopic theory for semiconductor quantum dots that explains the pronounced deviations from the prevalent point-dipole description that were recently observed in spectroscopic experiments on quantum dots in photonic…
Detailed electronic many-body configurations are extracted from quantitatively measured timeresolved nonlinear absorption spectra of resonantly excited GaAs quantum wells. The microscopic theory assigns the observed spectral changes to a…
Cavity quantum electrodynamics of multipartite systems is studied in depth, which consist of an arbitrary number of emitters in interaction with an arbitrary number of cavity modes. The governing model is obtained by taking the full…
The multipole expansion is a key tool in the study of light-matter interactions. All the information about the radiation of and coupling to electromagnetic fields of a given charge-density distribution is condensed into few numbers: The…
The photoluminescence polarizations of (In,Ga)As/GaAs quantum dots annealed at different temperatures are studied as a function of external magnetic field (Hanle curves). In these dependencies, remarkable resonant features appear due to…
The maximum-density-droplet (MDD) state of quantum-dot electrons becomes unstable at strong magnetic fields to the addition of interior holes. Using exact diagonalization, we demonstrate that the first hole is located at the center of the…
In a single quantum dot (QD), the electrons were driven out of thermal equilibrium by the back-action from a nearby quantum point contact (QPC). We found the driving to energy excited states can be probed with the random telegraph signal…
In quantum dots made from materials with nonzero nuclear spins, hyperfine coupling creates a fluctuating effective Zeeman field (Overhauser field) felt by electrons, which can be a dominant source of spin qubit decoherence. We characterize…
In this work, we investigate the electronic and optical properties of the b-AsP quantum dots(QDs) and quantum rings(QRs) with different edge types in the presence of an in-plane electric field and a perpendicular magnetic field utilizing…
Adiabatic time-dependent density functional theory fails for excitations of a heteroatomic molecule composed of two open-shell fragments at large separation. Strong frequency-dependence of the exchange-correlation kernel is necessary for…
We develop a theoretical description of transport through quantum dots connected to reservoirs via spin-polarized ballistic contacts. Rate equations account for spin accumulation inside the dot, electron-electron interactions, and…
The disordered potential landscape in an InGaAs/InAlAs two-dimensional electron gas patterned into narrow wires is investigated by means of scanning gate microscopy. It is found that scanning a negatively charged tip above particular sites…
We study the charge and spin density distributions of excitonic insulator (EI) states in the tight-binding approximation. We first discuss the charge and spin densities of the EI states when the valence and conduction bands are composed of…
We provide a theoretical description for the coupling between the intersubband excitations of a bi-dimensional electron gas with the electromagnetic field. This description, based on the electrical dipole gauge, applies to an arbitrary…
Excitations of ordered insulating magnets gain renewed interest due to their potential topological properties and the natural realization of magnetic analogues of the celebrated topological models. In this paper we go beyond these parallels…
We theoretically study spin and charge currents through finite-size two-dimensional $s$-wave superconductor/uniform ferromagnet/s-wave superconductor (SFS) junctions with intrinsic spin-orbit interactions (ISOIs) using a quasiclassical…
We study theoretically the performance of electrically pumped self-organized quantum dots as a gain material in the mid-IR range at room temperature. We analyze an AlGaAs/InGaAs based structure composed of dots-in-a-well sandwiched between…
A high-energy spin resonance mode is known to exist in many high-temperature superconductors. Motivated by recent scanning tunneling microscopy (STM) experiments in superconducting Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$, we study the effects of…