Related papers: Spin polarized parametric pumping
We investigate an adiabatic spin pumping through a quantum dot with a single orbital energy level under the Zeeman effect. Electron pumping is produced by two periodic time dependent parameters, a magnetic field and a difference of the…
Conventional spin pumping, driven by magnetization dynamics, is longitudinal since the pumped spin current flows normal to the interface between the ferromagnet and the conductor. We predict \textit{Hall-type/transverse} and…
An Archimedean screw is a classical pump that exploits the equivalence of rotation and translation in helices. Similarly, a spin spiral texture can pump charge and spin by rotating at a frequency $\omega$. In the present paper, we study…
A dc current can be pumped through an interacting system by periodically varying two independent parameters such as magnetic field and a gate potential. We present a formula for the adiabatic pumping current in general interacting systems,…
In this study, current pumping by an external potential is studied on the basis of the Keldysh Green's function method, and a pumping formula written in terms of retarded and advanced Green's functions is obtained. It is shown that pumping…
We investigate adiabatic charge pumping in disordered system in one dimension with open and closed boundary conditions. In contrast to the Thouless charge pumping, the system has no gap even though all the states are localized, i.e., strong…
Spin pumping driven by bistable exchange spin waves is demonstrated in a Pt/Y$_3$Fe$_5$O$_{12}$ film under parametric excitation. In the Pt/Y$_3$Fe$_5$O$_{12}$ film, the spin pumping driven by parametric excitation selectively enhances the…
Non-adiabatic pumping of discrete charges, realized by a dynamical quantum dot in an AlGaAs/GaAs heterostructure, is studied under influence of a perpendicular magnetic field. Application of an oscillating voltage in the GHz-range to one of…
We consider a small itinerant ferromagnet exposed to an external magnetic field and strongly driven by a thermally induced spin current. For this model, we derive the quasi-classical equations of motion for the magnetization where the…
Analogous to circular spin current in an isolated quantum loop, bias induced spin circular current can also be generated under certain physical conditions in a nanojunction having single and/or multiple loop geometries which we propose…
Nanoscopic rings pierced by external magnetic fields and asymmetrically connected to wires behave in sharp contrast with classical expectations. By studying the real-time evolution of tight-binding models in different geometries, we show…
In a nanomagnet (whose total spin S< 1000), very small polarized currents can lead to magnetic reversal. Treating on the same footing the transport and magnetic properties of a nanomagnet connected to magnetic leads via tunneling barriers,…
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…
We theoretically propose quantum spin pumping mediated by magnons, under a time-dependent transverse magnetic field, at the interface between a ferromagnetic insulator and a non-magnetic metal. The generation of a spin current under a…
We consider a classical overdamped Brownian particle moving in a symmetric periodic potential. We show that a net particle flow can be produced by adiabatically changing two external periodic potentials with a spatial and a temporal phase…
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…
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…
We develop a theory of adiabatic orbital pumping, highlighting qualitative differences from spin pumping. An oscillating magnetic field pumps not only orbital angular momentum current but also orbital angular position current. The latter,…
We have measured the statistical properties of magnetic reversal in nanomagnets driven by a spin-polarized current. Like reversal induced by a magnetic field, spin-transfer-driven reversal near room temperature exhibits the properties of…
We analyze the operation of a molecular machine driven by the non-adiabatic variation of external parameters. We derive a formula for the integrated flow from one configuration to another, obtain a "no-pumping theorem" for cyclic processes…