The ordering of quantum dots in three-dimensional quantum dot lattices is investigated by grazing-incidence small-angle X-ray scattering (GISAXS). Theoretical models describing GISAXS intensity distributions for three general classes of lattices of quantum dots are proposed. The classes differ in the type of disorder of the positions of the quantum dots. The models enable full structure determi...

Symmetry-breaking perturbations destabilize the critical points of the two-channel and two-impurity Kondo models, thereby leading to a crossover from non-Fermi liquid behavior to standard Fermi liquid physics. Here we use an analogy between this crossover and one occurring in the boundary Ising model to calculate the full crossover Green function analytically. In remarkable agreement with our n...

Electron transport through a system of two quantum dots connected in series is studied theoretically with the use of non-equilibrium Green function formalism based on the equation of motion method. Each dot is described by the one-level Anderson Hamiltonian and interdot Coulomb interactions in the form of the Hubbard-like term are taken into account. The electric current and occupation numbers ...

We present a detailed investigation into the optical characteristics of individual InAs quantum dots QDs grown by metalorganic chemical vapor deposition, with low temperature emission in the telecoms window around 1300 nm. Using microphotoluminescence PL spectroscopy we have identified neutral, positively charged, and negatively charged exciton and biexciton states. Temperature-dependent measur...

The zero–temperature conductance of diatomic molecule, modelled as a correlated double quantum dot attached to noninteracting leads is investigated. We utilize the Rejec–Ramšak formulas, relating the linear–response conductance to the ground–state energy dependence on magnetic flux within the framework of EDABI method, which combines exact diagonalization with ab initio calculations. The single...

We report the temperature dependence of the zero-bias conductance of a single-electron transistor in the regime of weak coupling between the quantum dot and the leads. The Fano line shape, convoluted with thermal broadening, provides a good fit to the observed asymmetric Coulomb charging peaks. However, the width of the peaks increases more rapidly than expected from the thermal broadening of t...

Inelastic transport through double quantum dot systems with coupling between electronic and vibrational degrees of freedom is examined by means of a master equation approach. The current and the conductance are analyzed for both weak and strong interdot couplings. The results show that an asymmetry in the current–voltage characteristic and appearance of negative differential conductance due to ...

three different nanostructured semiconductor lasers were studied – the quantum dot passively mode-locked laser, the dual-mode quantum dot laser and the optically-injected quantum dot distributed feedback laser. The key milestones achieved were: 1) the use of optical feedback to reduce the timing jitter of the pulsed lasers from 295 fs/cycle to 32 fs/cycle, 2) experimental determination of the o...

A highly sensitive charge detector is realized for a quantum dot in an InAs nanowire. We have developed a self-aligned etching process to fabricate in a single step a quantum point contact in a two-dimensional electron gas and a quantum dot in an InAs nanowire. The quantum dot is strongly coupled to the underlying point contact that is used as a charge detector. The addition of one electron to ...