The fluctuations and the distribution of the conductance peak spac-ings of a quantum dot in the Coulomb-blockade regime are studied and compared with the predictions of random matrix theory (RMT). The experimental data were obtained in transport measurements performed on a semiconductor quantum dot fabricated in a GaAs-AlGaAs heterostruc-ture. It is found that the fluctuations in the peak spaci...

Bonding and antibonding states of artificial molecules have been realized in experiments by directly coupling two quantum dots. Without a direct coupling between two nearby quantum dots, here we show that under a very unusual condition (i.e., a large asymmetrical couplings to the leads at a large bias) continuous coherence control of double-dot charge states can be achieved by changing the flux...

We present a theory of electronic properties of HgTe quantum dot and propose a strain sensor based on a strain-driven transition from a HgTe quantum dot with inverted bandstructure and robust topologically protected quantum edge states to a normal state without edge states in the energy gap. The presence or absence of edge states leads to large on/off ratio of conductivity across the quantum do...

– We suggest a series of transport experiments on spin precession in quantum dots coupled to one or two ferromagnetic leads. Dot spin states are created by spin injection and analyzed via the linear conductance through the dot, while an applied magnetic field gives rise to the Hanle effect. Such a Hanle experiment can be used to determine the spin lifetime in the quantum dot, to measure the spi...

We present a study on the effects of quantum dot coverage on the properties of InAs dots embedded in GaAs and in metamorphic In0.15Ga0.85As confining layers grown by molecular beam epitaxy on GaAs substrates. We show that redshifted emission wavelengths exceeding 1.3 μm at room temperature were obtained by the combined use of InGaAs confining layers and high quantum dot coverage. The use of hig...

The influence of interactions on electronic transport properties can be observed in many nanostructures, in particular in a so-called quantum dot, namely a spatially isolated island in and out of which electrons can tunnel. Due to its small size, the quantum dot supports discretely-spaced energy levels; considering only one of these levels for simplicity, we model the dot with the Hamiltonian H...

We present measurements of relative intensity noise versus various levels of optical feedback for 1.3 μm quantum dot lasers epitaxially grown on silicon for the first time. A systematic comparison is made with heterogeneously integrated 1.55 μm quantum well lasers on silicon. Our results indicate up to 20 dB reduced sensitivity of the quantum dot lasers on silicon compared to the quantum wells.

The focus of our effort has been to develop quantum information processing technologies based on a solid-state cavity QED platform consisting of quantum dots in photonic crystals. The main goals that we have accomplished include: 1. Study of the ultrafast dynamics of the quantum dot-cavity QED system [Majumdar et al., Phys. Rev. A, 2012], and ultrafast switching between two single photon pulses...