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Related papers: Spin pumping through quantum dots

200 papers

We study adiabatic pumping of electrons through quantum dots attached to ferromagnetic leads. Hereby we make use of a real-time diagrammatic technique in the adiabatic limit that takes into account strong Coulomb interaction in the dot. We…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Janine Splettstoesser , Michele Governale , Jürgen König

A quantum pump device involving magnetic barriers produced by the deposition of ferro magnetic stripes on hetero-structure's is investigated. The device for dc- transport does not provide spin-polarized currents, but in the adiabatic…

Quantum Physics · Physics 2007-05-23 Ronald Benjamin , Colin Benjamin

We present a general formalism to study adiabatic pumping through interacting quantum dots. We derive a formula that relates the pumped charge to the local, instantaneous Green function of the dot. This formula is then applied to the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Janine Splettstoesser , Michele Governale , Jürgen König , Rosario Fazio

We investigate spin and charge current through a quantum dot pumped by a time-varying magnetic field. Using the density matrix method, quantum rate equations for the electronic occupation numbers in the quantum dot are obtained and solved…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Zhao Yang Zeng , Hong Li , Baowen Li

We study non-adiabatic charge pumping through single-level quantum dots taking into account Coulomb interactions. We show how a truncated set of equations of motion can be propagated in time by means of an auxiliary-mode expansion. This…

Mesoscale and Nanoscale Physics · Physics 2012-01-12 Alexander Croy , Ulf Saalmann , Alexis R. Hernández , Caio H. Lewenkopf

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,…

Strongly Correlated Electrons · Physics 2015-06-25 Eran Sela , Yuval Oreg

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…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 R. Citro , N. Andrei , Q. Niu

We describe a novel mechanism for charge pumping through tunnel-coupled quantum dots in the regime of strong Coulomb blockade. The quantum state of an additional electron within the structure is steered by changing the tunneling couplings…

Condensed Matter · Physics 2009-11-07 F. Renzoni , T. Brandes

We investigate a non-adiabatic parametric quantum pump consists of a nonmagnetic scattering region connected by two ferromagnetic leads. The presence of ferromagnetic leads allows electrons with different spins to experience different…

Condensed Matter · Physics 2009-11-07 Wei Zheng , Junling Wu , Baigeng Wang , Jian Wang , Qingfeng Sun , Hong Guo

We propose and analyze a new scheme of realizing both spin filtering and spin pumping by using ac-driven double quantum dots in the Coulomb blockade regime. By calculating the current through the system we demonstrate that the spin…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Ernesto Cota , Ramon Aguado , Gloria Platero

Non-adiabatic charge pumping through a single-level quantum dot with periodically modulated parameters is studied theoretically. By means of a quantum-master-equation approach the full counting statistics of the system is obtained. We find…

Mesoscale and Nanoscale Physics · Physics 2016-04-22 Alexander Croy , Ulf Saalmann

A quantum pumping mechanism which produces dc current or voltage in response to a cyclic deformation of the confining potential in an open quantum dot is reported. The voltage produced at zero current bias is sinusoidal in the phase…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 M. Switkes , C. M. Marcus , K. Campman , A. C. Gossard

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…

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…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Colin Benjamin , Roberta Citro

We propose three different mechanisms for pumping spin-polarized currents in a ballistic circuit using a time-dependent magnetic field acting on an asymmetrically connected quantum ring at half filling. The first mechanism works thanks to a…

Mesoscale and Nanoscale Physics · Physics 2014-02-26 Michele Cini , Stefano Bellucci

We study resonant all-electric adiabatic spin pumping through a quantum dot with two nearby levels by using a Fermi liquid approach in the strongly interacting regime, combined with a projective numerical renormalization group (NRG) theory.…

Mesoscale and Nanoscale Physics · Physics 2013-12-17 C. P. Moca , A. Alex , A. Shnirman , G. Zarand

We investigate the influence of the Coulomb interaction on the adiabatic pumping current through quantum dots. Using nonequilibrium Green's functions techniques, we derive a general expression for the current based on the instantaneous…

Mesoscale and Nanoscale Physics · Physics 2009-09-16 A. R. Hernández , F. A. Pinheiro , C. H. Lewenkopf , E. R. Mucciolo

We propose a device acting as a spin valve which is based on a double quantum dot structure with parallel topology. Using the exact analytical solution for the noninteracting case we argue that, at a certain constellation of system…

Mesoscale and Nanoscale Physics · Physics 2010-03-18 J. P. Dahlhaus , S. Maier , A. Komnik

By combining Floquet theory with Green's function formalism, we present non-adiabatic quantum spin and charge pumping through a zigzag ferromagnetic graphene nanoribbon including a double-barriers structure driven weakly by two local $ac$…

Mesoscale and Nanoscale Physics · Physics 2015-09-25 Hosein Cheraghchi

In a mesoscopic system, under zero bias voltage, a finite charge is transferred by quantum adiabatic pumping by adiabatically and periodically changing two or more control parameters. We obtained expressions for the pumped charge for a ring…

Mesoscale and Nanoscale Physics · Physics 2016-09-22 Masahiko Taguchi , Satoshi Nakajima , Toshihiro Kubo , Yasuhiro Tokura