Related papers: A spin pump turnstile: parametric pumping of a spi…
We propose a four-terminal device designed to manipulate by all electrical means the spin of a magnetic adatom positioned at the edge of a quantum spin Hall insulator. We show that an electrical gate, able to tune the interface resistance…
Controlling the flow of spin and charge currents in topological insulators (TIs) is a crucial requirement for applications in quantum computation and spin electronics. We demonstrate that such control can be established in nanoscopic…
We analyze the charge and spin pumping in an interacting dot within the almost adiabatic limit. By using a non-equilibrium Green's function technique within the time-dependent slave boson approximation, we analyze the pumped current in…
We examine transport through a quantum dot coupled to three ferromagnetic leads in the regime of weak tunnel coupling. A finite source-drain voltage generates a nonequilibrium spin on the otherwise non-magnetic quantum dot. This spin…
We study DC charge and spin transport through a weakly coupled quantum dot, driven by a non-adiabatic periodic change of system parameters. We generalize the model of Tien and Gordon to simultaneously oscillating voltages and tunnel…
We demonstrate that a quantum spin Hall current, spontaneously generated at the edge of a two-dimensional topological insulator, acts as a source of spin-pumping for a magnetic impurity with uniaxial anisotropy. One can then manipulate the…
The adiabatic topological pumping is proposed by periodically modulating a semiconductor nanowire double-quantum-dot chain. We demonstrate that the quantized charge transport can be achieved by a nontrivial modulation of the quantum-dot…
We study the thermoelectric response of a device containing a pair of helical edge states contacted at the same temperature $T$ and chemical potential $\mu$ and connected to an external reservoir, with different chemical potential and…
We study two different parametric pumps for interacting quantum wires, one for pumping spin currents, the other for charge currents. We find that the spin or charge pumped per cycle has a non-universal crossover, depending on pumping…
It is shown that, for appropriate values of electron energy, the silicene dot can work as a controllable spin polarizer. The spin polarizer can polarize the spin of transmitted electrons from nearly pure down to nearly pure up by changing…
We calculate adiabatic charge and spin pumping through a serial double quantum dot with strong Coulomb interaction, coupled to normal metal or ferromagnetic contacts. We use a real-time diagrammatic approach in the regime of weak coupling…
We demonstrate a spin pump to generate pure spin current of tunable intensity and polarization in the absence of charge current. The pumping functionality is achieved by means of an ac gate voltage that modulates the Rashba constant…
We propose a device based on an antidot embedded in a narrow quantum wire in the edge state regime, that can be used to inject and/or to control spin polarized current. The operational principle of the device is based on the effect of…
Nuclear spin polarization can be pumped into spin-blocked quantum dots by multiple Landau- Zener passages through singlet-triplet anticrossings. By numerical simulations of realistic systems including approximately $10^7$ nuclear spins…
Spin pumping is a recently established means for generating a pure spin current, whereby spins are pumped from a magnet into the adjacent target material under the ferromagnetic resonance condition. We theoretically investigate the spin…
We study charge and spin pumping in an interacting one-dimensional wire. We show that a spatially periodic potential modulated in space and time acts as a quantum pump inducing a dc-current component at zero bias. The current generated by…
We design spin filters for particles with potentially arbitrary spin S (= 1/2, 1, 3/2,....) using a one-dimensional periodic chain of magnetic atoms as a quantum device. Describing the system within a tight-binding formalism we present an…
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 quantum dot with spin-orbit interaction can work as an efficient spin filter if it is connected to N (> 2) external leads via tunnel barriers. When an unpolarized current is injected to a quantum dot from a lead, polarized currents are…
Semiconductor quantum dots (QDs) offer a platform to explore the physics of quantum electronics including spins. Electron spins in QDs are considered good candidates for quantum bits in quantum information processing, and spin control and…