The Coherent Transport Properties of Electrons in a 4-Terminal Nano Device with Rashba Spin-Orbit Coupling in the Presence of Magnetic Field

We investigate the coherent transport properties of electrons in a side terminal of a four-terminal nano device made of quantum wires with Rashba spin-orbit (SO) coupling in the presence of magnetic filed. We numerically calculate the charge and spin conductances dependent on SO coupling strength and reduced flux. The results imply that the coherent transport in this device is determined by the interplay of Rashba SO coupling and magnetic filed. For specific values of magnetic flux and SO coupling strength, a complete blocking can take place. It also shows that there is a de-blocking phenomenon induced by the interplay of magnetic flux and SO coupling. Such a 4-terminal and multi-channel structure may provide more options of controlling methods for the coherent charge and spin transport.

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Rashba spin-orbit coupling in InGaAs/InP quantum wires

MRS Proceedings ◽

10.1557/proc-825-g5.7 ◽

2004 ◽

Vol 825 ◽

Author(s):

Jens Knobbe ◽

Vitaliy A. Guzenko ◽

Thomas Schäpers

Keyword(s):

Quantum Wires ◽

Orbit Coupling ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

One Dimensional ◽

Rashba Spin ◽

Wet Chemical ◽

Wet Chemical Etching ◽

The One ◽

Rashba Coupling

AbstractThe effect of Rashba spin-orbit coupling on the transport properties of InGaAs/InP quantum wire structures is investigated. The geometry of the wire structures was defined by selective wet chemical etching. For wires without a gate a clear beating pattern, due to the presence of the Rashba spin-orbit coupling, is observed for wires with a width down to 600 nm. For narrower wires no beating pattern is found. The experimental observations are explained by contribution of the Rashba spin-orbit coupling to the one-dimensional magnetosubbands. By depleting the one-dimensional conductor by means of a gate electrode the Rashba coupling strength could be controlled.

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TRANSPORT THROUGH INTERACTING AHARONOV–BOHM–CASHER INTERFEROMETERS

International Journal of Modern Physics B ◽

10.1142/s0217979211101247 ◽

2011 ◽

Vol 25 (22) ◽

pp. 3019-3025

Author(s):

QING-QIANG XU ◽

BEN-LING GAO ◽

SHI-JIE XIONG

Keyword(s):

Magnetic Flux ◽

Electronic Transport ◽

Transport Processes ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Spin Filter ◽

Rashba Spin ◽

Mesoscopic Ring ◽

Universal Regime ◽

Aharonov Bohm

We investigate the transport properties of an interacting ring threaded by a magnetic flux and with Rashba spin-orbit coupling, based on a recently developed functional renormalized group technique. In the calculations of the electronic transport processes, the Coloumb On-site interactions are taken into account. For an interacting ring connected to two leads, we find that (i) for ΦAC = 0, the behavior of transmission zero at ΦAB = π is generic for the universal regime; (ii) for certain ΦAC and ΦAB, one can use the mesoscopic ring as spin filter even in the presence of the local interaction in the ring.

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Transport properties in a multi-terminal regular polygonal quantum ring with Rashba spin—orbit coupling

Chinese Physics B ◽

10.1088/1674-1056/21/12/120303 ◽

2012 ◽

Vol 21 (12) ◽

pp. 120303 ◽

Cited By ~ 4

Author(s):

Han-Zhao Tang ◽

Li-Xue Zhai ◽

Jian-Jun Liu

Keyword(s):

Transport Properties ◽

Orbit Coupling ◽

Quantum Ring ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Rashba Spin

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The Side Effect of Spin Precession and Quantum Interference in a Four-Terminal Nano Device with Rashba Spin-Orbit Coupling

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.496.351 ◽

2012 ◽

Vol 496 ◽

pp. 351-354

Author(s):

Hui Xian Wang ◽

Li Ben Li ◽

Da Wei Kang

Keyword(s):

Side Effect ◽

Quantum Interference ◽

Quantum Wires ◽

Combined Effect ◽

Spin Precession ◽

Spatial Distributions ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Rashba Spin ◽

Coherent Transmission

We propose a four-terminal nano device made of quantum wires with Rashba spin-orbit (SO) coupling. In each terminal there are several independent channels formed with quantum wires. The coherent transmission of electrons in such a nano system is a combined effect of quantum interference and spin precession. When defining two opposite terminals as source and drain leads, the charge and spin currents in channels of other two terminals exhibit spatial distributions which reflect the competition between spin precession and quantum interference during the tunneling of electrons. Since the four-terminal nano device is geometrically simple for the moving paths of charge and spin, our investigation may shed some light on the basic physical picture on this issue.

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SPIN POLARIZATION AND TUNNELING MAGNETORESISTANCE IN FERROMAGNETIC/SEMICONDUCTOR/FERROMAGNETIC HETEROSTRUCTURE

Modern Physics Letters B ◽

10.1142/s0217984908017199 ◽

2008 ◽

Vol 22 (27) ◽

pp. 2667-2676 ◽

Cited By ~ 1

Author(s):

DE LIU ◽

HONGMEI ZHANG

Keyword(s):

Spin Polarization ◽

Coupling Strength ◽

Channel Length ◽

Ferromagnetic Semiconductor ◽

Orbit Coupling ◽

Tunneling Magnetoresistance ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Rashba Spin ◽

Left And Right

Based on the coherent quantum transport theory, the spin polarization and tunneling magnetoresistance for polarized electrons through ferromagnetic/semiconductor/ferromagnetic (FM/SM/FM) heterostructure are studied theoretically within the Landauer framework of ballistic transport. The significant quantum size, quantum coherent, angle between the magnetic moments of the left and right ferromagnets, and Rashba spin-orbit interaction are considered simultaneously. The results indicate that the spin polarization and tunneling magnetoresistance are periodic functions of the semiconductor channel length, quasiperiodic functions of the Rashba spin-orbit coupling strength, and depend on the relative orientation of the two magnetizations in the left and right ferromagnets. A moderate angle, semiconductor channel length, and Rashba spin-orbit coupling strength allow a giant spin polarization or tunneling magnetoresistance. The results may be of relevance for the implementation of quasi-one-dimensional spin-transistor devices.

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