相关论文: Far-infrared absorption of self-assembled semicond…
We have employed time-dependent local-spin density theory to analyze the far-infrared transmission spectrum of InAs self-assembled nano-rings recently reported [A. Lorke et al, cond-mat/9908263 (1999)]. The overall agreement between theory…
Motivated by recent experiments [A. Lorke {\em et al.}, Phys. Rev. Lett.\ {\bf 84}, 2223 (2000)] an analysis of the ground state and far-infrared absorption of two electrons confined in a quantum ring is presented. The height of the…
We investigate the effects of the shape of quantum dots on their far-infrared absorption in an external magnetic field by a model calculation. We focus our attention on dots with a parabolic confinement potential deviating from the common…
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…
We study effects of electron-electron interactions and confinement potential on the magneto-optical absorption spectrum in the far-infrared range of lateral quantum dot molecules. We calculate far-infrared (FIR) spectra for three different…
A strongly asymmetric, Fano-like resonance profile has been found for magneto-absorption in the states of hot free electron-hole pairs scattered by defects in bulk semiconductors. The renormalization of the absorption profile, compared to…
We present theoretical results on far-infrared (FIR) absorption of single-electron transistors. Based on them, we propose and explain how to conduct combined FIR--dc-transport experiments to determine the charging energy and other relevant…
We study the effects of electron-electron correlations and confinement potential on the far-infrared spectrum of a lateral two-electron quantum dot molecule by exact diagonalization. The calculated spectra directly reflect the lowered…
We investigate the far-infrared (FIR) absorption of a two-dimensional electron gas in a periodically modulated quantizing magnetic field. The magnetic field varies along only one spatial direction and the external time-dependent electric…
We have investigated experimentally and theoretically the far-infrared (FIR) absorption of gated, deep-mesa-etched GaAs/Al$_x$Ga$_{1-x}$As quantum wires. To overcome Kohn's theorem we have in particular prepared double-layered wires and…
Recent photoabsorption measurements have revealed a rich fine structure in the collective charge-density excitation spectrum of few-electron quantum dots in the presence of magnetic fields. We have performed systematic computational studies…
Modulated electroreflectance spectroscopy $\Delta R/R$ of semiconductor self-assembled quantum dots is investigated. The structure is modeled as dots with lens shape geometry and circular cross section. A microscopic description of the…
A resonance behaviour of the far infrared absorption probability at a frequency \sim N^{1/4} is predicted for clusters of N electron-hole pairs (2\le N\le 110) confined in disk-shaped quantum dots. For radially symmetric dots, the…
We present an experimental demonstration of closed-loop quantum parameter estimation in which real-time feedback is used to achieve robustness to modeling uncertainty. By performing broadband estimation of a magnetic field acting on…
We review a number of recent experiments which are probing ground state and excitations of few-electron systems in self-assembled InAs quantum dots. Far-infrared spectroscopy, together with local as well as large-scale capacitive probing…
We use magnetotunnelling spectroscopy as a non-invasive probe to produce two-dimensional spatial images of the probability density of an electron confined in a self-assembled semiconductor quantum dot. The images reveal clearly the…
We study the effect of magnetic field and geometric confinement on excitons confined to a quantum ring. We use analytical matrix elements of the Coulomb interaction and diagonalize numerically the effective-mass Hamiltonian of the problem.…
We consider an effective mass model for an electron-hole pair in a simplified confinement potential, which is applicable to both a nanoscopic self-assembled semiconducting InAs ring and a quantum dot. The linear optical susceptibility,…
Here we embark on a thorough investigation of the magneto-optical absorption in semiconducting {\em spherical} quantum dots characterized by a confining harmonic potential and an applied magnetic field in the symmetric gauge. This is done…
The conduction band electron states of laterally-coupled semiconductor quantum rings are studied within the frame of the effective mass envelope function theory. We consider the effect of axial and in-plane magnetic fields for several…