相关论文: On the optical Stark effect of excitons in InGaAs …
We investigate high resolution laser absorption spectroscopy of a single InGaAs/GaAs self-assembled quantum dot embedded in a field-effect structure. We show experimentally that the interband optical absorption to the lower Zeeman branch of…
The fine structure of the neutral exciton in a single self assembled InGaAs quantum dot is investigated under the effect of a lateral electric field. Stark shifts up to 1.5 meV, an increase in linewidth, and a decrease in photoluminescence…
Two-photon resonant excitation of the biexciton-exciton cascade in a quantum dot generates highly polarization-entangled photon pairs in a near-deterministic way. However, the ultimate level of achievable entanglement is still debated.…
Spatially structured light fields applied to semiconductor quantum dots yield fundamentally different absorption spectra than homogeneous beams. In this paper, we theoretically discuss the resulting spectra for different light beams using a…
We present results of correlated pseudopotential calculations of an exciton in a pair of vertically stacked InGaAs/GaAs dots. Competing effects of strain, geometry, and band mixing lead to many unexpected features missing in contemporary…
We report on single InGaAs quantum dots embedded in a lateral electric field device. By applying a voltage we tune the neutral exciton transition into resonance with the biexciton using the quantum confined Stark effect. The results are…
The full time-dependent four-wave mixing polarization in quantum dots is microscopically calculated, taking into account acoustic phonon-assisted transitions between different exciton states of the dot. It is shown that quite different…
The demonstration of degeneracy of the exciton spin states is an important step towards the production of entangled photons pairs from the biexciton cascade. We measure the fine structure of exciton and biexciton states for a large number…
Within the framework of adiabatic approximation, the energy levels and direct interband light absorption in a strongly prolated ellipsoidal quantum dot are studied. Analytical expressions for the particle energy spectrum and absorption…
Excitons confined to flat semiconductor quantum dots with elliptical cross section are considered as we study geometrical effects on exciton binding energy, electron-hole separation, and the resulting linear optical properties. We use…
The optical properties of excitons confined in initially-unstrained GaAs/AlGaAs quantum dots are studied as a function of a variable quasi-uniaxial stress. To allow the validation of state-of-the-art computational tools for describing the…
We investigate theoretically the spatial dependence of the linear absorption spectra of single and coupled semiconductor quantum dots, where the strong three-dimensional quantum confinement leads to an overall enhancement of Coulomb…
We investigate site-controlled In$_{0.25}$Ga$_{0.75}$As quantum dots in (111)B GaAs pyramidal recesses as spin qubits. Combining scanning confocal cryomicroscopy, magneto-photoluminescence studies and resonant excitation, we identify and…
A detailed theoretical study of the optical absorption in self-assembled quantum dots is presented in this paper. A rigorous atomistic strain model as well as a sophisticated electronic band structure model are used to ensure accurate…
We investigate experimentally and theoretically the resonant emission of single InAs/GaAs quantum dots in a planar microcavity. Due to the presence of at least one residual charge in the quantum dots, the resonant excitation of the neutral…
As an alternative to commonly used electrical methods, we have investigated the optical pumping of charged exciton complexes addressing impurity related transitions with photons of the appropriate energy. Under these conditions, we…
We investigate the optical emission and decay dynamics of excitons confined in large strain-free GaAs quantum dots grown by droplet epitaxy. From time-resolved measurements combined with a theoretical model we show that droplet-epitaxy…
We have measured the oscillator strength and quantum efficiency of excitons confined in large InGaAs quantum dots by recording the spontaneous emission decay rate while systematically varying the distance between the quantum dots and a…
The dynamics of an exciton-LO-phonon system after an ultrafast optical excitation in an InAs/GaAs quantum dot is studied theoretically. Influence of anharmonic phonon damping and its interplay with the phonon dispersion is analyzed. The…
A transition from a cylindrical quantum dot to a highly elongated quantum dash is theoretically studied here with an atomistic approach combining empirical tight binding for single particle states and configuration interaction method for…