NONLOCAL ELECTRONIC SPIN DETECTION, SPIN ACCUMULATION AND THE SPIN HALL EFFECT

In recent years, electrical spin injection and detection has grown into a lively area of research in the field of spintronics. Spin injection into a paramagnetic material is usually achieved by means of a ferromagnetic source, whereas the induced spin accumulation or associated spin currents are detected by means of a second ferromagnet or the reciprocal spin Hall effect, respectively. This article reviews the current status of this subject, describing both recent progress and well-established results. The emphasis is on experimental techniques and accomplishments that brought about important advances in spin phenomena and possible technological applications. These advances include, amongst others, the characterization of spin diffusion and precession in a variety of materials, such as metals, semiconductors and graphene, the determination of the spin polarization of tunneling electrons as a function of the bias voltage, and the implementation of magnetization reversal in nanoscale ferromagnetic particles with pure spin currents.

Download Full-text

Pure spin currents in Ge probed by inverse spin-Hall effect

AIP Advances ◽

10.1063/1.4973392 ◽

2017 ◽

Vol 7 (5) ◽

pp. 055907

Author(s):

F. Bottegoni ◽

C. Zucchetti ◽

M. Finazzi ◽

G. Isella ◽

F. Ciccacci

Keyword(s):

Hall Effect ◽

Spin Hall Effect ◽

Pure Spin ◽

Spin Currents ◽

Inverse Spin Hall Effect

Download Full-text

Studying pure spin currents in weakly spin-orbit coupled materials using the pulsed ferromagnetic resonance driven inverse spin-Hall effect (Conference Presentation)

Spintronics XII ◽

10.1117/12.2529892 ◽

2019 ◽

Author(s):

Christoph M. Boehme ◽

Marzieh Kavand ◽

Kipp van Schooten ◽

Dali Sun ◽

Hans Malissa ◽

...

Keyword(s):

Hall Effect ◽

Ferromagnetic Resonance ◽

Spin Hall Effect ◽

Pure Spin ◽

Spin Orbit ◽

Spin Currents ◽

Inverse Spin Hall Effect

Download Full-text

PERFECT ALLOYS FOR SPIN HALL CURRENT-INDUCED MAGNETIZATION SWITCHING

SPIN ◽

10.1142/s2010324712500105 ◽

2012 ◽

Vol 02 (02) ◽

pp. 1250010 ◽

Cited By ~ 16

Author(s):

MARTIN GRADHAND ◽

DMITRY V. FEDOROV ◽

PETER ZAHN ◽

INGRID MERTIG ◽

YOSHICHIKA OTANI ◽

...

Keyword(s):

Hall Effect ◽

Noble Metals ◽

Spin Diffusion ◽

Spin Current ◽

Material Design ◽

Spin Hall Effect ◽

Pure Spin ◽

Magnetization Switching ◽

Hall Angle ◽

Electronic Measurement

We propose a device that allows for magnetization switching in nanomagnets by means of a pure spin current induced by the spin Hall effect. For this purpose we combine the ideas of magnetization switching of a ferromagnet by a spin current produced via the spin accumulation at a ferromagnet/nonmagnet interface with the electronic measurement of the direct spin Hall effect, and the theoretical material design to identify systems with a large spin Hall angle and an appropriate spin diffusion length. We will discuss the device design with respect to the size of the charge and spin currents. Based on ab initio calculations, we predict dilute alloys ideally suited for this application. Noble metals with single-sheeted Fermi surfaces, doped with either heavy impurities like Bi and Pb in Cu or Bi in Ag and light impurities like C and N in Au , seem to be the best candidates for a spin Hall angle larger than 5%.

Download Full-text

Enhanced spin accumulation in nano-pillar-based lateral spin valve using spin reservoir effect

Journal of Physics D Applied Physics ◽

10.1088/1361-6463/ac47bf ◽

2022 ◽

Author(s):

Xiaomin Cui ◽

Shaojie Hu ◽

Takashi Kimura

Keyword(s):

Spin Diffusion ◽

Spin Injection ◽

Spin Valve ◽

Spin Current ◽

Spin Valves ◽

Pure Spin ◽

Spin Accumulation ◽

Spintronic Devices ◽

High Bias ◽

Angle Deposition

Abstract Lateral spin valves are ideal nanostructures for investigating spin-transport physics phenomena and promoting the development of future spintronic devices owing to dissipation-less pure spin current. The magnitude of the spin accumulation signal is well understood as a barometer for characterizing spin current devices. Here, we develop a novel fabrication method for lateral spin valves based on ferromagnetic nanopillar structures using a multi-angle deposition technique. We demonstrate that the spin-accumulation signal is effectively enhanced by reducing the lateral dimension of the nonmagnetic spin channel. The obtained results can be quantitatively explained by the confinement of the spin reservoir by considering spin diffusion into the leads. The temperature dependence of the spin accumulation signal and the influence of the thermal spin injection under a high bias current are also discussed.

Download Full-text

Manipulation of spin currents in metallic systems

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2011.0010 ◽

2011 ◽

Vol 369 (1948) ◽

pp. 3136-3149 ◽

Cited By ~ 28

Author(s):

Yoshichika Otani ◽

Takashi Kimura

Keyword(s):

Room Temperature ◽

Spin Diffusion ◽

Diffusion Processes ◽

Spin Injection ◽

Spin Current ◽

Hybrid Structures ◽

Pure Spin ◽

Spin Currents ◽

Magnetic Metal ◽

Hall Effect Measurements

The transport properties of diffusive spin currents have been investigated in lateral ferromagnetic/non-magnetic metal hybrid structures. The spin diffusion processes were found to be strongly dependent on the magnitude of the spin resistances of connected materials. Efficient spin injection and detection are accomplished by optimizing the junction structures on the basis of the spin resistance circuitry. The magnetization switching of a nanoscale ferromagnetic particle and also room temperature spin Hall effect measurements were realized by using an efficient pure-spin-current injection.

Download Full-text

Anomalous spin Hall and inverse spin Hall effects in magnetic systems

Communications Physics ◽

10.1038/s42005-021-00557-9 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

X. R. Wang

Keyword(s):

Hall Effect ◽

Order Parameter ◽

Spin Current ◽

Spin Hall Effect ◽

Magnetic Systems ◽

Charge Current ◽

Spin Currents ◽

Tensor Quantity ◽

Hall Effects ◽

Spin Hall Effects

AbstractSpin current is a very important tensor quantity in spintronics. However, the well-known spin-Hall effect (SHE) can only generate a few of its components whose propagating and polarization directions are perpendicular with each other and to an applied charge current. It is highly desirable in applications to generate spin currents whose polarization can be in any possible direction. Here anomalous SHE and inverse spin-Hall effect (ISHE) in magnetic systems are predicted. Spin currents, whose polarisation and propagation are collinear or orthogonal with each other and along or perpendicular to the charge current, can be generated, depending on whether the applied charge current is along or perpendicular to the order parameter. In anomalous ISHEs, charge currents proportional to the order parameter can be along or perpendicular to the propagating or polarization directions of the spin current.

Download Full-text