SPIN INTERFERENCE IN RASHBA 2DEG SYSTEMS

The gate controllable SOI provides useful information about spin interference.1 Spin interference effects are studied in two different interference loop structures. It is known that sample specific conductance fluctuations affect the conductance in the interference loop. By using array of many interference loops, we carefully pick up TRS Altshuler-Aronov-Spivak (AAS)-type oscillation which is not sample specific and depends on the spin phase. The experimentally obtained gate voltage dependence of AAS oscillations indicates that the spin precession angle can be controlled by the gate voltage.2 We demonstrate the time reversal Aharonov-Casher (AC) effect in small arrays of mesoscopic rings.3 By using an electrostatic gate we can control the spin precession angle rate and follow the AC phase over several interference periods. We also see the second harmonic of the AC interference, oscillating with half the period. The spin interference is still visible after more than 20π precession angle. We have proposed a Stern-Gerlach type spin filter based on the Rashba SOI.4 A spatial gradient of effective magnetic field due to the nonuniform SOI separates spin up and down electrons. This spin filter works even without any external magnetic fields and ferromagnetic contacts. We show the semiconductor/ferromagnet hybrid structure is an effective way to detect magnetization process of submicron magnets. The problem of the spin injection from ferromagnetic contact into 2DEG is also disicussed. Note from Publisher: This article contains the abstract only.

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Gate-Voltage-Modulated Spin Precession in Graphene/WS2 Field-Effect Transistors

Electronics ◽

10.3390/electronics10222879 ◽

2021 ◽

Vol 10 (22) ◽

pp. 2879

Author(s):

Amir Muhammad Afzal ◽

Muhammad Farooq Khan ◽

Jonghwa Eom

Keyword(s):

Field Effect ◽

Field Effect Transistors ◽

Spin Precession ◽

Orbital Interaction ◽

Transition Metal Dichalcogenide ◽

Precession Angle ◽

Spin Orbital ◽

Spintronic Devices ◽

Non Local ◽

Spin Fet

Transition metal dichalcogenide materials are studied to investigate unexplored research avenues, such as spin transport behavior in 2-dimensional materials due to their strong spin-orbital interaction (SOI) and the proximity effect in van der Waals (vdW) heterostructures. Interfacial interactions between bilayer graphene (BLG) and multilayer tungsten disulfide (ML-WS2) give rise to fascinating properties for the realization of advanced spintronic devices. In this study, a BLG/ML-WS2 vdW heterostructure spin field-effect transistor (FET) was fabricated to demonstrate the gate modulation of Rashba-type SOI and spin precession angle. The gate modulation of Rashba-type SOI and spin precession has been confirmed using the Hanle measurement. The change in spin precession angle agrees well with the local and non-local signals of the BLG/ML-WS2 spin FET. The operation of a spin FET in the absence of a magnetic field at room temperature is successfully demonstrated.

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On the control of optical spin injection by tuning the band gap offset in magnetic/non-magnetic hybrid structure

Optics & Laser Technology ◽

10.1016/j.optlastec.2014.01.001 ◽

2014 ◽

Vol 60 ◽

pp. 22-26

Author(s):

M. Ghali

Keyword(s):

Band Gap ◽

Spin Injection ◽

Hybrid Structure

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Sample-Specific Conductance Fluctuations Modulated by the Superconducting Phase

Physical Review Letters ◽

10.1103/physrevlett.76.4592 ◽

1996 ◽

Vol 76 (24) ◽

pp. 4592-4595 ◽

Cited By ~ 55

Author(s):

S. G. den Hartog ◽

C. M. A. Kapteyn ◽

B. J. van Wees ◽

T. M. Klapwijk ◽

W. van der Graaf ◽

...

Keyword(s):

Specific Conductance ◽

Superconducting Phase ◽

Conductance Fluctuations

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Spin-filter transport and magnetic properties in a binuclear Cu(ii) expanded porphyrin based molecular junction

Dalton Transactions ◽

10.1039/c9dt01312a ◽

2019 ◽

Vol 48 (23) ◽

pp. 8418-8426 ◽

Cited By ~ 3

Author(s):

Nicolás Montenegro-Pohlhammer ◽

Rodrigo Urzúa-Leiva ◽

Dayán Páez-Hernández ◽

Gloria Cárdenas-Jirón

Keyword(s):

Magnetic Properties ◽

Transport Properties ◽

Gate Voltage ◽

Molecular Junction ◽

Spin Filter ◽

Expanded Porphyrin

The Spin-filter transport properties of a magnetically coupled, binuclear Cu(ii) expanded porphyrin based molecular junction, were studied at different bias and gate voltage values, through the DFT-NEGF methodology.

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Directional Dependence of Spin Currents Induced by Aharonov–Casher Phase

International Journal of Modern Physics B ◽

10.1142/s021797929800123x ◽

1998 ◽

Vol 12 (20) ◽

pp. 2091-2102 ◽

Cited By ~ 14

Author(s):

Taeseung Choi ◽

Chang-Mo Ryu ◽

A. M. Jayannavar

Keyword(s):

Current Flow ◽

Solid Angle ◽

Spin Current ◽

Spin Precession ◽

Precession Angle ◽

Effective Spin ◽

Periodic Behavior ◽

Spin Currents ◽

Open Ring ◽

Aharonov Bohm

We have calculated the persistent spin current of an open ring induced by the Aharonov–Casher phase. For unpolarized electrons there exist no persistent charge currents, but persistent spin currents. We show that, in general, the magnitude of the persistent spin current in a ring depends on the direction of the direct current flow from one reservoir to another. The persistent spin current is modulated by the cosine function of the spin precession angle. The nonadiabatic Aharonov–Casher phase gives anomalous behaviors. The Aharonov–Anandan phase is determined by the solid angle of spin precession. When the nonadiabatic Aharonov–Anandan phase approaches a constant value with the increase of the electric field, the periodic behavior of the spin persistent current occurs in an adiabatic limit. In this limit the periodic behavior of the persistent spin current could be understood by the effective spin-dependent Aharonov–Bohm flux.

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