Semiconductor quantum dots have long been described as artificial atoms because they have discrete energy states analogous to the energy levels of natural atoms. In recent years, it has become possible to create coupled pairs of quantum dots that are analogous to natural diatomic molecules. These artificial molecules have received a great deal of attention because of the potential applications ...

We study a single-electron transistor (SET) based upon a II-VI semiconductor quantum dot doped with a single-Mn ion. We present evidence that this system behaves like a quantum nanomagnet whose total spin and magnetic anisotropy depend dramatically both on the number of carriers and their orbital nature. Thereby, the magnetic properties of the nanomagnet can be controlled electrically. Converse...

We show that electron and hole Landé g factors in self-assembled III-V quantum dots have a rich structure intermediate between that of paramagnetic atomic impurities and bulk semiconductors. Strain, dot geometry, and confinement energy modify the effective g factors, yet are insufficient to explain our results. We find that the dot's discrete energy spectrum quenches the orbital angular momentu...

We demonstrate single-shot readout of a silicon quantum dot spin qubit, and we measure the spin relaxation time T1. We show that the rate of spin loading can be tuned by an order of magnitude by changing the amplitude of a pulsed-gate voltage, and the fraction of spin-up electrons loaded can also be controlled. This tunability arises because electron spins can be loaded through an orbital excit...

We investigate the electronic transport through a single-level quantum-dot which is capacitively coupled to a charge-qubit. By employing the method of nonequilibrium Green's functions, we calculate the electric current through quantum dot at finite bias voltages. The Green's functions and self-energies of the system are calculated perturbatively and self-consistently to the second order of inte...

We show that the conductance of a quantum wire side-coupled to a quantum dot, with a gate potential favoring the formation of a dot magnetic moment, is a universal function of the temperature. Universality prevails even if the currents through the dot and the wire interfere. We apply this result to the experimental data of Sato et al. [Phys. Rev. Lett. 95, 066801 (2005)]. Nanodevices owe much o...

In this paper we consider electromagnetic field quantization in the presence of a dispersive and absorbing semiconductor quantum dot. By using macroscopic approach and Green's function method, quantization of electromagnetic field is investigated. Interaction of a two-level atom , which is doped in a semiconductor quantum dot, with the quantized field is considered and its spontaneous emission ...

the electronic conductance at zero temperature through a quantum wire with side-connected asymmetric quantum ring (as a scatter system) is theoretically studied using the non-interacting hamiltonian anderson tunneling method. in this paper we concentrate on the configuration of the quantum dot rings. we show that the asymmetric structure of qd-scatter system strongly influences the amplitude an...

Electron states are studied for quantum dots in a strained Si quantum well, taking into account both valley and orbital physics. Realistic geometries are considered, including circular and elliptical dot shapes, parallel and perpendicular magnetic fields, and most importantly for valley coupling the small local tilt of the quantum-well interface away from the crystallographic axes. In absence o...