Related papers: Heterogeneous confinement in laterally coupled InG…
We performed charge detection on a lateral triple quantum dot with star-like geometry. The setup allows us to interpret the results in terms of two double dots with one common dot. One double dot features weak tunnel coupling and can be…
We present a study of the electronic structure of two laterally coupled gaussian quantum dots filled with two particles. The exact diagonalization method has been used in order to inspect the spatial correlations and examine the particular…
Using single-particle pseudopotential and many-particle configuration interaction methods, we compare various physical quantities of (In,Ga)As/GaAs quantum dot molecules (QDMs) made of dissimilar dots (heteropolar QDMs) with QDMs made of…
Free standing beams containing a two-dimensional electron system are shaped from a GaAs/AlGaAs heterostructure. Quantum point contacts and (double) quantum dots are laterally defined using metal top gates. We investigate the electronic…
Molecular states in a SINGLE PAIR of strongly coupled self-assembled InAs quantum dots are investigated using a sub-micron sized single electron transistor containing just a few pairs of coupled InAs dots embedded in a GaAs matrix. We…
We study the electronic coupling between two vertically stacked InAs quantum dots, which are embedded in the center of a n-i-n structure. We use a micro-photoluminescence setup to optically isolate a single quantum dot pair and measure the…
We demonstrate an efficient method to engineer the quantum confinement in a system of two quantum dots grown in a vertical stack. We achieve this by using materials with a different lattice constant for the growth of the outer and inner…
We have studied a system consisted of two coupled quantum dots containing two electrons subjected by a laser field. The effect of the laser is described by the dressed-band approach involving the concept of the conduction/valence effective…
The transport spectrum of a strongly tunnel-coupled one-electron double quantum dot electrostatically defined in a GaAs/AlGaAs heterostructure is studied. At finite source-drain-voltage we demonstrate the unambiguous identification of the…
We present experimental magnetotunneling results and atomistic pseudopotential calculations of quasiparticle electron and hole wave functions of self-assembled InAs/GaAs quantum dots. The combination of a predictive theory along with the…
We provide a physical analysis of the charging and detection of the first few electrons in a laterally-coupled GaAs/AlGaAs quantum dot (LCQD) circuit with integrated quantum point contact (QPC) read-out. Our analysis is based on the…
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…
Single lateral InGaAs quantum dot molecules have been embedded in a planar micro-cavity in order to increase the luminescence extraction efficiency. Using a combination of metal-organic vapor phase and molecular beam epitaxy samples could…
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…
Most self-assembled quantum dot molecules are intrinsically asymmetric with inequivalent dots resulting from imperfect control of crystal growth. We have grown vertically-aligned pairs of InAs/GaAs quantum dots by molecular beam epitaxy,…
In-plane magnetic field photoluminescence spectra from a series of GaAs/AlGaAs coupled double quantum wells show distinctive doublet structures related to the symmetric and antisymmetric states. The magnetic field behavior of the upper…
We demonstrate the real-time detection of single photogenerated electrons in two different lateral double quantum dots made in AlGaAs/GaAs/AlGaAs quantum wells having a thin or a thick AlGaAs barrier layer. The observed incident laser power…
We study a new system in which electrons in two dimensions are confined by a non homogeneous magnetic field. The system consists of a heterostructure with on top of it a superconducting disk. We show that in this system electrons can be…
We present photoluminescence studies of the molecular neutral biexciton-exciton spectra of individual vertically stacked InAs/GaAs quantum dot pairs. We tune either the hole or the electron levels of the two dots into tunneling resonances.…
Confinement of the electron gas along one of the spatial directions opens an avenue for studying fundamentals of quantum transport along the side of numerous practical electronic applications, with high-electron-mobility transistors being a…