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Related papers: Tunable pure spin currents in a triple-quantum-dot…

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We demonstrate that the combined effect of a spatially periodic potential, lateral confinement and spin-orbit interaction gives rise to a quantum ratchet mechanism for spin-polarized currents in two-dimensional coherent conductors. Upon…

Mesoscale and Nanoscale Physics · Physics 2007-11-07 Matthias Scheid , Andreas Pfund , Dario Bercioux , Klaus Richter

We present a theory of spin, electronic and transport properties of a few-electron lateral triangular triple quantum dot molecule in a magnetic field. Our theory is based on a generalization of a Hubbard model and the Linear Combination of…

Strongly Correlated Electrons · Physics 2010-03-11 F. Delgado , Y. -P. Shim , M. Korkusinski , P. Hawrylak

We present a generalize Landauer-B\"uttiker transport theory for multi-terminal spin transport in presence of spin-orbit interaction. It is pointed out that the presence of spin-orbit interaction results in {\it equilibrium spin currents},…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 T. P. Pareek

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…

Mesoscale and Nanoscale Physics · Physics 2009-08-06 Chia-Hui Lin , Chi-Shung Tang , Yia-Chung Chang

We calculate the current-voltage characteristic of a one-dimensional band insulator with magnetic field and Rashba spin-orbit coupling which is connected to nonmagnetic leads. Without spin-orbit coupling we find a complete spin-filtering…

Mesoscale and Nanoscale Physics · Physics 2011-12-02 Thibaut Jonckheere , George Japaridze , Thierry Martin , Roland Hayn

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

Using standard quantum network method, we analytically investigate the effect of Rashba spin-orbit coupling (RSOC) and a magnetic field on the spin transport properties of a polygonal quantum ring. Using Landauer-Buttiker formula, we have…

Mesoscale and Nanoscale Physics · Physics 2015-06-18 Han-Zhao Tang , Li-Xue Zhai , Man Shen , Jian-Jun Liu

In a quantum ring connected with two external leads the spin properties of an incoming electron are modified by the spin-orbit interaction resulting in a transformation of the qubit state carried by the spin. The ring acts as a one qubit…

Quantum Physics · Physics 2009-11-10 Peter Foldi , Balazs Molnar , Mihaly G. Benedict , F. M. Peeters

We report an unconventional behavior of electron transport in the limit of zero magnetic flux in a one-dimensional disordered ring, be it completely random or any correlated one, subjected to Rashba spin-orbit (SO) coupling. It exhibits…

Mesoscale and Nanoscale Physics · Physics 2016-12-20 Moumita Patra , Santanu K. Maiti

We propose a novel approach to explore the properties of a quantum dot in the presence of the spin-orbit interaction and in a tilted magnetic field. The spin-orbit coupling within the quantum dot manifest itself as anti-crossing of the…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Hong-Yi Chen , Vadim Apalkov , Tapash Chakraborty

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

In this paper we report on a tuneable few electron lateral triple quantum dot design. The quantum dot potentials are arranged in series. The device is aimed at studies of triple quantum dot properties where knowing the exact number of…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 L. Gaudreau , A. Kam , G. Granger , S. A. Studenikin , P. Zawadzki , A. S. Sachrajda

We investigate the electronic transport through two parallel double quantum dots coupled both capacitively and via a perpendicularly aligned charge qubit. The presence of the qubit leads to a modification of the coherent tunnel amplitudes…

Mesoscale and Nanoscale Physics · Physics 2012-06-19 Christian Nietner , Gernot Schaller , Christina Pöltl , Tobias Brandes

We consider a single-level quantum dot coupled to two leads which are ferromagnetic in general. Apart from tunneling processes conserving electron spin, we also include processes associated with spin-flip of tunneling electrons, which…

Mesoscale and Nanoscale Physics · Physics 2018-08-22 Łukasz Karwacki , Józef Barnaś

We calculate current, spin current and tunnel magnetoresistance (TMR) for a quantum dot coupled to ferromagnetic leads in the presence of a square wave of bias voltage. Our results are obtained via time-dependent nonequilibrium Green…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 F. M. Souza , J. A. Gomez

Quantum dot arrays provide a promising platform for quantum information processing. For universal quantum simulation and computation, one central issue is to demonstrate the exhaustive controllability of quantum states. Here, we report the…

We demonstrate how the Rashba spin-orbit coupling in semiconductor heterostructures can produce and control a spin-polarized current without ferromagnetic leads. Key idea is to use spin-double refraction of an electronic beam with a nonzero…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 V. Marigliano Ramaglia , D. Bercioux , V. Cataudella , G. De Filippis , C. A. Perroni

We report a study of spin dependent transport in a system composed of a quantum dot coupled to a normal metal lead and a ferromagnetic lead (NM-QD-FM). We use the master equation approach to calculate the spin-resolved currents in the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 F. M. Souza , J. C. Egues , A. P. Jauho

We study the nonequilibrium spin transport through a quantum dot containing two spin levels coupled to the magnetic electrodes. A formula for the spin-dependent current is obtained and is applied to discuss the linear conductance and…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Ping Zhang , Qi-Kun Xue , Yu-Peng Wang , X. C. Xie

We investigate the effect of strong spin-orbit interaction on the electronic transport through non-magnetic impurities in one-dimensional systems. When a perpendicular magnetic field is applied, the electron spin polarization becomes…

Materials Science · Physics 2007-05-23 R. G. Pereira , E. Miranda