Related papers: Electrically controlled quantum dot based spin cur…
We consider low temperature transport through a lateral quantum dot asymmetrically coupled to two conducting leads, and tuned to the mixed-valence region separating two adjacent Coulomb blockade valleys with spin S=1/2 and S=1 on the dot.…
A nanodevice capable of separating spins of two electrons confined in a quantum dot formed in a gated semiconductor nanowire is proposed. Two electrons confined initially in a single quantum dot in the singlet state are transformed into the…
We present an approach for entangling spin qubits via capacitive coupling mediated by an ac electric field-driven multielectron mediator quantum dot. To illustrate this method, we consider the case of a driven two-electron dot that mediates…
By operating a one-electron quantum dot (fabricated between a multielectron dot and a one-electron reference dot) as a spectroscopic probe, we study the spin properties of a gate-controlled multielectron GaAs quantum dot at the transition…
A method of switching a controlled-NOT gate in a solid-stae NMR quantum computer is presented. Qubits of I=1/2 nuclear spins are placed periodically along a quantum spin chain (1-D antiferromagnet) having a singlet ground state with a…
We present a set of concrete and realistic ideas for the implementation of a small-scale quantum computer using electron spins in lateral GaAs/AlGaAs quantum dots. Initialization is based on leads in the quantum Hall regime with tunable…
An alternating electric field, applied to a quantum dot, couples to the electron spin via the spin-orbit interaction. We analyze different types of spin-orbit coupling known in the literature and find two efficient mechanisms of spin…
In this paper we show that it is possible to switch the spin polarization of the photocurrent signal obtained from a single self-assembled quantum dot photodiode under the effect of elliptically polarized light by just increasing the light…
The polarization of conduction electron spins due to an electrical current is observed in strained nonmagnetic semiconductors using static and time-resolved Faraday rotation. The density, lifetime, and orientation rate of the…
Spintronics devices rely on spin-dependent transport behavior evoked by the presence of spin-polarized electrons. Transport through nanostructures, on the other hand, is dominated by strong Coulomb interaction. We study a model system in…
We propose a novel spin filter based on a graphene nanoring fabricated above a ferromagnetic strip. The exchange interaction between the magnetic moments of the ions in the ferromagnet and the electron spin splits the electronic states, and…
We investigate two schemes for pumping spin adiabatically from a ferromagnet through an interacting quantum dot into a normal lead, which exploit the possibility to vary in time the ferromagnet's magnetization, either its amplitude or its…
A new way of getting controlled spin dependent transport through a two-terminal bridge setup is explored. The system comprises a magnetic quantum ring which is directly coupled to a magnetic quantum wire and subjected to an in-plane…
The backscattering process of injected electrons on exchange-splitted levels of quantum well (QW) in ferromagnetic metal / insulator / semiconductor heterostructure is studied. It is found that, if one of the exchange-splitted levels lies…
We propose two new approaches for regulating spin polarization and spin inversion in a conducting junction within a tight-binding framework based on wave-guide theory. The system comprises a magnetic quantum ring with finite modulation in…
A two-electron system confined in two coupled semiconductor quantum dots is investigated as a candidate for performing quantum logic operations on spin qubits. We study different processes of swapping the electron spins by controlled…
A pure spin current injector is proposed based on adiabatic pumping and crossed normal/Andreev reflection. The device consists of a three-terminal ferromagnet-superconductor-semiconductor system in which the injection of a pure spin current…
We have studied theoretically the possibility of ultra-fast manipulation of a single electron spin in 2D semiconductor quantum dots, by means of high-frequency time-dependent electric fields. The electron spin degree of freedom is excited…
Diode is a key device in electronics: the charge current can flow through the device under a forward bias, while almost no current flows under a reverse bias. Here we propose a corresponding device in spintronics: the spin-current diode, in…
The creation, coherent manipulation, and measurement of spins in nanostructures open up completely new possibilities for electronics and information processing, among them quantum computing and quantum communication. We review our…