Related papers: Spin-Related Current Suppression in a Semiconducto…
We investigated the peculiarities of non-equilibrium charge configurations in the system of two strongly coupled quantum dots (QDs) weakly connected to the reservoirs in the presence of Coulomb correlations. We revealed that total electron…
We show theoretically that a strongly spin-polarized current can be generated in semiconductors by taking advantage of the ferromagnetic phase of a quantum dot array (QDA). A Hubbard model with coupling to leads is used to study the…
The spin-polarized transport through two-level quantum dots weakly coupled to ferromagnetic leads is considered theoretically in the Coulomb blockade regime. It is assumed that the dot is doubly occupied, so that the current flows due to…
We investigated the electron transport properties of parallel-coupled double quantum dot (DQD) devices under magnetic fields. When a low magnetic field was applied, electron tunneling through parallel-coupled DQDs was observed. Under a high…
Kondo correlations are responsible for the emergence of a zero-bias peak in the low temperature differential conductance of Coulomb blockaded quantum dots. In the presence of a global SU(2)$\otimes$SU(2) symmetry, which can be realized in…
Systems of quantum dots (QD) connected to leads exhibit periodic conductance peaks as a function of gate voltage arising from the Coulomb blockade effect \cite{review1,review2,review3}. Much effort goes into minimizing the size of QDs and…
We investigated the tunneling current peculiarities in the system of two coupled by means of the external field quantum dots (QDs) weakly connected to the electrodes in the presence of Coulomb correlations. It was found that tuning of the…
We theoretically investigate the quantum transport properties of a triangular triple quantum dot (TTQD) ring connected with two reservoirs by means of analytical derivation and accurate hierarchical-equations-of-motion calculation. A…
We consider the production of mobile and nonlocal pairwise spin-entangled electrons from tunneling of a BCS-superconductor (SC) to two normal Fermi liquid leads. The necessary mechanism to separate the two electrons coming from the same…
We implement silicon quantum dot devices with two layers of gate electrodes using a self-alignment technique, which allows for ultra-small gate lengths and intrinsically perfect layer-to-layer alignment. In a double quantum dot system, we…
Transport properties of a gated nanostructure depend crucially on the coupling of its states to the states of electrodes. In the case of a single quantum dot the coupling, for a given quantum state, is constant or can be slightly modified…
We investigate current fluctuations in a three-terminal quantum dot in the sequential tunneling regime. Dynamical spin blockade can be induced when the spin-degeneracy of the dot states is lifted by a magnetic field. This results in…
We propose a simple setup of three coupled quantum dots in the Coulomb blockade regime as a source for spatially separated currents of spin-entangled electrons. The entanglement originates from the singlet ground state of a quantum dot with…
We study the nonequilibrium spin transport through a quantum dot containing two spin levels coupled to the magnetic electrodes. A formula for the spin-dependent current is obtained and is applied to discuss the linear conductance and…
We demonstrate an electric-field control of tunneling magnetoresistance (TMR) effect in a semiconductor quantum-dot (QD) spin-valve device. By using ferromagnetic Ni nano-gap electrodes, we observe the Coulomb blockade oscillations at a…
The spin-polarized transport through a coherent strongly coupled double quantum dot (DQD) system is analyzed theoretically in the sequential and cotunneling regimes. Using the real-time diagrammatic technique, we analyze the current,…
The non-Fermi-liquid properties of an ultrasmall quantum dot coupled to a lead and to a quantum box are investigated. Tuning the ratio of the tunneling amplitudes to the lead and box, we find a line of two-channel Kondo fixed points for…
Electronic transport through a two-path triple-quantum-dot system with two source leads and one drain is studied. By separating the conductance of the two double dot paths, we are able to observe double dot and triple dot physics in…
Motivated by the recent discovery of a canyon of conductance suppression in a two-level equal spin quantum dot system [Phys. Rev. Lett. $\bf{104}$, 186804 (2010)] the transport through this system is studied in detail. At low bias and low…
We theoretically investigate charge transport through serial double quantum dots (SDQDs) with strong electron correlations using nonequilibrium Green's function techniques. In the linear response regime, we compute the charge stability…