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Related papers: Quantum Dot as a Spin--Current Diode

200 papers

Based on Keldysh's nonequilibrium Green function method, the spin-dependent transport properties in a ferromagnet-quantum dot (QD)-ferromagnet coupled system are investigated. It is shown the spin current shows quite different…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Hai-Feng Mu , Gang Su , Qing-Rong Zheng

We study the spin-resolved transport properties of T-shaped double quantum dots coupled to ferromagnetic leads. Using the numerical renormalization group method, we calculate the linear conductance and the spin polarization of the current…

Mesoscale and Nanoscale Physics · Physics 2015-06-22 K. P. Wojcik , I. Weymann

We present a theory of magnetotransport through a system of two coupled electronic orbitals, where the electron spin interacts with a (large) local magnetic moment via an exchange interaction. For the physical realization of such a set-up…

Mesoscale and Nanoscale Physics · Physics 2012-11-06 Klemens Mosshammer , Gerold Kiesslich , Tobias Brandes

Current fluctuations can provide additional insight into quantum transport in mesoscopic systems. The present work is carried out for the fluctuation properties of transport through a pair of coupled quantum dots which are connected with…

Mesoscale and Nanoscale Physics · Physics 2009-09-02 JunYan Luo , Xin-Qi Li , YiJing Yan

We study the spin-dependent transport through a quantum dot coupled to two ferromagnetic electrodes using the equation of motion method for the nonequilibrium Green's functions. Our results show that the conductance and the density of…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Huanwen Lai , Xuean Zhao , Zhu-An Xu , You-Quan Li

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…

Mesoscale and Nanoscale Physics · Physics 2018-05-09 Jürgen König , Jan Martinek , Jozef Barnas , Gerd Schön

We investigate the linear and nonlinear transport through a single level quantum dot connected to two ferromagnetic leads in Kondo regime, using the slave-boson mean field approach for finite on-site Coulomb repulsion. We find that for…

Condensed Matter · Physics 2007-05-23 Jing Ma , Bing Dong , X. L. Lei

We study the Kondo effect in the electron transport through a quantum dot coupled to ferromagnetic leads, using a real-time diagrammatic technique which provides a systematic description of the nonequilibrium dynamics of a system with…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Yasuhiro Utsumi , Jan Martinek , Gerd Schön , Hiroshi Imamura , Sadamichi Maekawa

We present a theoretical study of low temperature nonequilibrium transport through an interacting quantum dot in the presence of Zeeman magnetic field and current injection into one of its leads. By using a self-consistent renormalized…

Mesoscale and Nanoscale Physics · Physics 2017-01-27 Shaon Sahoo , Adeline Crépieux , Mireille Lavagna

We analyze cotunneling transport through two quantum dots in series weakly coupled to external ferromagnetic leads. In the Coulomb blockade regime the electric current flows due to third-order tunneling, while the second-order…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 I. Weymann

The zero bias conductance of quantum dots coupled to ferromagnetic leads is investigated. In the strong coupling regime, it is found that the conductance is a non-monotonic function of the angle between the magnetisation directions in the…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 J. Fransson

We propose a new approximation scheme within equation of motion approach (EOM) to spin polarized transport through a quantum dot coupled to ferromagnetic leads. It has some advantages over a widely used in the literature standard EOM…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Mariusz Krawiec

Manipulation of the spin-states of a quantum dot by purely electrical means is a highly desirable property of fundamental importance for the development of spintronic devices such as spin-filters, spin-transistors and single-spin memory as…

Mesoscale and Nanoscale Physics · Physics 2008-10-20 J. R. Hauptmann , J. Paaske , P. E. Lindelof

It was proposed that a double quantum dot can be used to be a detector of spin bias. Electron transport through a double quantum dot is investigated theoretically when a pure spin bias is applied on two conducting leads contacted to the…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Qing-feng Sun , Yanxia Xing , Shun-Qing Shen

A correct general formula for the spin current through an interacting quantum dot coupled to ferromagnetic leads with magnetization at an arbitrary angle $\theta$ is derived within the framework of the Keldysh formalism. Under asymmetric…

Mesoscale and Nanoscale Physics · Physics 2009-03-18 Hao Zhang , Guang-Ming Zhang , Lu Yu

Based on Keldysh non-equilibrium Green function method, we have investigated spin current production in a hybrid T-shaped device, consisting of a central quantum dot connected to the leads and a side dot which only couples to the central…

Mesoscale and Nanoscale Physics · Physics 2018-03-14 I. L. Fernandes , G. G. Cabrera

We discuss the possibility to generate, manipulate, and probe single spins in single-level quantum dots coupled to ferromagnetic leads. The spin-polarized currents flowing between dot and leads lead to a non-equilibrium spin accumulation,…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Matthias Braun , Jürgen König , Jan Martinek

We investigate non-linear magneto-transport through a single level quantum dot coupled to ferromagnetic leads, where the electron spin is coupled to a large, external (pseudo)spin via an anisotropic exchange interaction. We find regimes…

Mesoscale and Nanoscale Physics · Physics 2012-04-12 Carlos López-Monís , Clive Emary , Gerold Kiesslich , Gloria Platero , Tobias Brandes

We present a theoretical study based on the Anderson model of the transport properties of a Kondo impurity (atom or quantum dot) connected to ferromagnetic leads, which can sustain a non-equilibrium spin current. We analyze the case where…

Mesoscale and Nanoscale Physics · Physics 2013-10-08 Jong Soo Lim , Rosa Lopez , Laurent Limot , Pascal Simon

We investigate the linear and nonlinear dc transport through an interacting quantum dot connected to two ferromagnetic electrodes around Kondo regime with spin-flip scattering in the dot. Using a slave-boson mean field approach for the…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Jing Ma , X. L. Lei