Off-centred immobile magnetic vortex under influence of spin-transfer torque

This chapter defines a magnetic domain wall (DW) as the transition region where the direction of magnetic moments gradually change between two neighbouring domains. It has been pointed out that ferromagnetic materials are not necessarily magnetized to saturation in the absence of an external magnetic field. Instead, they have magnetic domains, within each of which magnetic moments align. The formation of the magnetic domains is energetically favourable because this structure can lower the magnetostatic energy originating from the dipole–dipole interaction. A magnetic vortex realized in a ferromagnetic disk is a typical example of nonuniform magnetic structure. In very small ferromagnetic systems, where a curling spin configuration has been proposed to occur in place of domains, the formation of DWs is not energetically favored.

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Current-induced magnetic vortex motion by spin-transfer torque

Physical Review B ◽

10.1103/physrevb.73.020403 ◽

2006 ◽

Vol 73 (2) ◽

Cited By ~ 106

Author(s):

Junya Shibata ◽

Yoshinobu Nakatani ◽

Gen Tatara ◽

Hiroshi Kohno ◽

Yoshichika Otani

Keyword(s):

Vortex Motion ◽

Spin Transfer Torque ◽

Spin Transfer ◽

Magnetic Vortex

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Reversal process of a magnetic vortex core under the combined action of a perpendicular field and spin transfer torque

Applied Physics Letters ◽

10.1063/1.4790841 ◽

2013 ◽

Vol 102 (6) ◽

pp. 062401 ◽

Cited By ~ 17

Author(s):

N. Locatelli ◽

A. E. Ekomasov ◽

A. V. Khvalkovskiy ◽

Sh. A. Azamatov ◽

K. A. Zvezdin ◽

...

Keyword(s):

Vortex Core ◽

Spin Transfer Torque ◽

Spin Transfer ◽

Magnetic Vortex ◽

Reversal Process ◽

Combined Action ◽

Perpendicular Field

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Introduction of spin torques

10.1093/oso/9780198787075.003.0019 ◽

2017 ◽

Author(s):

T. Kimura

Keyword(s):

Angular Momentum ◽

Giant Magnetoresistance ◽

Spontaneous Magnetization ◽

Magnetic Domain ◽

Magnetic Multilayers ◽

Transfer Effect ◽

Spin Transfer Torque ◽

Spin Transfer ◽

Spin Angular Momentum ◽

Spin Torques

This chapter discusses the spin-transfer effect, which is described as the transfer of the spin angular momentum between the conduction electrons and the magnetization of the ferromagnet that occurs due to the conservation of the spin angular momentum. L. Berger, who introduced the concept in 1984, considered the exchange interaction between the conduction electron and the localized magnetic moment, and predicted that a magnetic domain wall can be moved by flowing the spin current. The spin-transfer effect was brought into the limelight by the progress in microfabrication techniques and the discovery of the giant magnetoresistance effect in magnetic multilayers. Berger, at the same time, separately studied the spin-transfer torque in a system similar to Slonczewski’s magnetic multilayered system and predicted spontaneous magnetization precession.

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Analytical study of spin current density and spin-transfer torque in semi-Dirac heterostructures

Journal of Magnetism and Magnetic Materials ◽

10.1016/j.jmmm.2021.168117 ◽

2021 ◽

pp. 168117

Author(s):

Abbas Zarifi ◽

Moslem Zare

Keyword(s):

Current Density ◽

Analytical Study ◽

Spin Current ◽

Spin Transfer Torque ◽

Spin Transfer

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Field-free and sub-ns magnetization switching of magnetic tunnel junctions by combining spin-transfer torque and spin–orbit torque

Applied Physics Letters ◽

10.1063/5.0039061 ◽

2021 ◽

Vol 118 (9) ◽

pp. 092406

Author(s):

Chaoliang Zhang ◽

Yutaro Takeuchi ◽

Shunsuke Fukami ◽

Hideo Ohno

Keyword(s):

Tunnel Junctions ◽

Magnetic Tunnel Junctions ◽

Spin Transfer Torque ◽

Spin Transfer ◽

Spin Orbit ◽

Magnetization Switching

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Control of Structural and Magnetic Properties of Polycrystalline Co2FeGe Films via Deposition and Annealing Temperatures

Nanomaterials ◽

10.3390/nano11051229 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1229

Author(s):

Andrii Vovk ◽

Sergey A. Bunyaev ◽

Pavel Štrichovanec ◽

Nikolay R. Vovk ◽

Bogdan Postolnyi ◽

...

Keyword(s):

Magnetic Properties ◽

Spin Transfer Torque ◽

Spin Transfer ◽

Post Deposition Annealing ◽

Structure Variation ◽

Annealing Temperatures ◽

Damping Parameter ◽

Soft Ferromagnetic ◽

Thin Polycrystalline ◽

Post Deposition

Thin polycrystalline Co2FeGe films with composition close to stoichiometry have been fabricated using magnetron co-sputtering technique. Effects of substrate temperature (TS) and post-deposition annealing (Ta) on structure, static and dynamic magnetic properties were systematically studied. It is shown that elevated TS (Ta) promote formation of ordered L21 crystal structure. Variation of TS (Ta) allow modification of magnetic properties in a broad range. Saturation magnetization ~920 emu/cm3 and low magnetization damping parameter α ~ 0.004 were achieved for TS = 573 K. This in combination with soft ferromagnetic properties (coercivity below 6 Oe) makes the films attractive candidates for spin-transfer torque and magnonic devices.

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