Spin-orbit torque and Dzyaloshinskii–Moriya interaction in 4d metal Rh-based magnetic heterostructures

AbstractDzyaloshinskii–Moriya interaction (DMI) is considered as one of the most important energies for specific chiral textures such as magnetic skyrmions. The keys of generating DMI are the absence of structural inversion symmetry and exchange energy with spin–orbit coupling. Therefore, a vast majority of research activities about DMI are mainly limited to heavy metal/ferromagnet bilayer systems, only focusing on their interfaces. Here, we report an asymmetric band formation in a superlattices (SL) which arises from inversion symmetry breaking in stacking order of atomic layers, implying the role of bulk-like contribution. Such bulk DMI is more than 300% larger than simple sum of interfacial contribution. Moreover, the asymmetric band is largely affected by strong spin–orbit coupling, showing crucial role of a heavy metal even in the non-interfacial origin of DMI. Our work provides more degrees of freedom to design chiral magnets for spintronics applications.

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Reducing Dzyaloshinskii-Moriya interaction and field-free spin-orbit torque switching in synthetic antiferromagnets

Nature Communications ◽

10.1038/s41467-021-23414-3 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Ruyi Chen ◽

Qirui Cui ◽

Liyang Liao ◽

Yingmei Zhu ◽

Ruiqi Zhang ◽

...

Keyword(s):

Domain Wall ◽

Tunnel Junctions ◽

Low Power Consumption ◽

Stray Field ◽

Magnetic Memory ◽

Spin Orbit ◽

Theoretic Analysis ◽

Spintronic Devices ◽

Deterministic Switching ◽

Moriya Interaction

AbstractPerpendicularly magnetized synthetic antiferromagnets (SAF), possessing low net magnetization and high thermal stability as well as easy reading and writing characteristics, have been intensively explored to replace the ferromagnetic free layers of magnetic tunnel junctions as the kernel of spintronic devices. So far, utilizing spin-orbit torque (SOT) to realize deterministic switching of perpendicular SAF have been reported while a large external magnetic field is typically needed to break the symmetry, making it impractical for applications. Here, combining theoretic analysis and experimental results, we report that the effective modulation of Dzyaloshinskii-Moriya interaction by the interfacial crystallinity between ferromagnets and adjacent heavy metals plays an important role in domain wall configurations. By adjusting the domain wall configuration between Bloch type and Néel type, we successfully demonstrate the field-free SOT-induced magnetization switching in [Co/Pd]/Ru/[Co/Pd] SAF devices constructed with a simple wedged structure. Our work provides a practical route for utilization of perpendicularly SAF in SOT devices and paves the way for magnetic memory devices with high density, low stray field, and low power consumption.

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Theoretical Conditions for Field-free Magnetization Switching Induced by Spin-orbit Torque and Dzyaloshinskii-Moriya Interaction

IEEE Electron Device Letters ◽

10.1109/led.2020.3043293 ◽

2020 ◽

pp. 1-1

Author(s):

Min Wang ◽

Zhaohao Wang ◽

Xueying Zhang ◽

Weisheng Zhao

Keyword(s):

Spin Orbit ◽

Magnetization Switching ◽

Moriya Interaction

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Relation of the Dzyaloshinskii-Moriya interaction to spin currents and to the spin-orbit field

Physical Review B ◽

10.1103/physrevb.96.054403 ◽

2017 ◽

Vol 96 (5) ◽

Cited By ~ 17

Author(s):

Frank Freimuth ◽

Stefan Blügel ◽

Yuriy Mokrousov

Keyword(s):

Spin Orbit ◽

Spin Currents ◽

Moriya Interaction

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Characterization of Spin-Orbit Torque Efficiency in Magnetic Heterostructures with Perpendicular Magnetic Anisotropy via Spin-Torque Ferromagnetic Resonance

Physical Review Applied ◽

10.1103/physrevapplied.13.034041 ◽

2020 ◽

Vol 13 (3) ◽

Cited By ~ 2

Author(s):

Jinwu Wei ◽

Congli He ◽

Xiao Wang ◽

Hongjun Xu ◽

Yizhou Liu ◽

...

Keyword(s):

Magnetic Anisotropy ◽

Ferromagnetic Resonance ◽

Perpendicular Magnetic Anisotropy ◽

Spin Torque ◽

Spin Orbit ◽

Magnetic Heterostructures

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Giant Dzyaloshinskii-Moriya interaction in Rashba superlattices

10.21203/rs.3.rs-39851/v1 ◽

2020 ◽

Author(s):

Woo-Seung Ham ◽

Abdul-Muizz Pradipto ◽

Kay Yakushiji ◽

Kwangsu Kim ◽

Sonny Rhim ◽

...

Keyword(s):

Heavy Metal ◽

Material Design ◽

Orbit Coupling ◽

Inversion Symmetry ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Band Formation ◽

Stacking Order ◽

Magnetic Skyrmions ◽

Moriya Interaction

Abstract Dzyaloshinskii-Moriya interaction (DMI) is considered as one of the most important energy for specific chiral texture such as magnetic skyrmions. The key of generating DMI is absence of structural inversion symmetry and exchange energy with spin-orbit coupling. Therefore, a vast majority of researches about DMI is mainly limited to heavy metal/ferromagnet bilayer systems, only focusing on their interfaces. Here, we report that asymmetric band formation in an artificial superlattice arises from inversion symmetry breaking in stacking order of atomic layers, resulting in bulk DMI. Such bulk DMI is more than 300% larger than simple sum of interfacial contribution. Moreover, the asymmetric band is largely affected by strong spin-orbit coupling, showing crucial role of a heavy metal even in the non-interfacial origin of DMI. Such Rashba superlattices can be a new class of material design for spintronics applications.

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Engineering magnetic heterostructures to obtain large spin Hall efficiency for spin-orbit torque devices

Applied Physics Letters ◽

10.1063/1.5036836 ◽

2018 ◽

Vol 113 (2) ◽

pp. 022402 ◽

Cited By ~ 6

Author(s):

Lisen Huang ◽

Shikun He ◽

Qi Jia Yap ◽

Sze Ter Lim

Keyword(s):

Spin Orbit ◽

Magnetic Heterostructures ◽

Large Spin

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S=12triangular-lattice antiferromagnetsBa3CoSb2O9andCsCuCl3: Role of spin-orbit coupling, crystalline electric field effect, and Dzyaloshinskii-Moriya interaction

Physical Review B ◽

10.1103/physrevb.94.214408 ◽

2016 ◽

Vol 94 (21) ◽

Cited By ~ 9

Author(s):

A. Sera ◽

Y. Kousaka ◽

J. Akimitsu ◽

M. Sera ◽

T. Kawamata ◽

...

Keyword(s):

Electric Field ◽

Field Effect ◽

Orbit Coupling ◽

Electric Field Effect ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Crystalline Electric Field ◽

Moriya Interaction

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First-principles Dzyaloshinskii–Moriya interaction in a non-collinear framework

Scientific Reports ◽

10.1038/s41598-020-77219-3 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

R. Cardias ◽

A. Szilva ◽

M. M. Bezerra-Neto ◽

M. S. Ribeiro ◽

A. Bergman ◽

...

Keyword(s):

First Principles ◽

Real Space ◽

Orbit Coupling ◽

Magnetic Configuration ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Atomic Sphere ◽

Sphere Approximation ◽

Atomic Sphere Approximation ◽

Moriya Interaction

AbstractWe have derived an expression of the Dzyaloshinskii–Moriya interaction (DMI), where all the three components of the DMI vector can be calculated independently, for a general, non-collinear magnetic configuration. The formalism is implemented in a real space—linear muffin-tin orbital—atomic sphere approximation (RS-LMTO-ASA) method. We have chosen the Cr triangular trimer on Au(111) and Mn triangular trimers on Ag(111) and Au(111) surfaces as numerical examples. The results show that the DMI (module and direction) is drastically different between collinear and non-collinear states. Based on the relation between the spin and charge currents flowing in the system and their coupling to the non-collinear magnetic configuration of the triangular trimer, we demonstrate that the DMI interaction can be significant, even in the absence of spin-orbit coupling. This is shown to emanate from the non-collinear magnetic structure, that can induce significant spin and charge currents even with spin-orbit coupling is ignored.

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