Constituents of magnetic anisotropy and a screening of spin–orbit coupling in solids

Abstract Magnetic anisotropy in strontium iridate (Sr2IrO4) is essential because of its strong spin–orbit coupling and crystal field effect. In this paper, we present a detailed mapping of the out-of-plane (OOP) magnetic anisotropy in Sr2IrO4 for different sample orientations using torque magnetometry measurements in the low-magnetic-field region before the isospins are completely ordered. Dominant in-plane anisotropy was identified at low fields, confirming the b axis as an easy magnetization axis. Based on the fitting analysis of the strong uniaxial magnetic anisotropy, we observed that the main anisotropic effect arises from a spin–orbit-coupled magnetic exchange interaction affecting the OOP interaction. The effect of interlayer exchange interaction results in additional anisotropic terms owing to the tilting of the isospins. The results are relevant for understanding OOP magnetic anisotropy and provide a new way to analyze the effects of spin–orbit-coupling and interlayer magnetic exchange interactions. This study provides insight into the understanding of bulk magnetic, magnetotransport, and spintronic behavior on Sr2IrO4 for future studies.

Download Full-text

On the magnetic anisotropy and susceptibility of Fe(NH 4 SO 4 ) 2 , 6H 2 O

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1961.0071 ◽

1961 ◽

Vol 261 (1305) ◽

pp. 207-214 ◽

Cited By ~ 20

Keyword(s):

Thermal Expansion ◽

Magnetic Anisotropy ◽

Crystal Lattice ◽

Crystal Field ◽

Coupling Coefficient ◽

Orbit Coupling ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Anisotropic Part ◽

Free Ion

The theory of magnetic anisotropy and susceptibility of Fe 2+ in Tutton salts has been worked out on the basis of Abragam & Pryce’s method. It is found that the anisotropic part of the crystal field changes with temperature owing to the thermal expansion of the crystal lattice. The spin-orbit coupling coefficient has to be decreased by ~ 20 % from its free ion value of - 103 cm -1 which indicates some amount of overlap between the 3 d -Fe 2+ and 8 - and p -O 2- charge clouds. The agreement of the theoretical values with the experiment is good within the limitations of the approximations involved.

Download Full-text

Spin-Orbit Coupling and Magnetic Anisotropy in Iron-Based Superconductors

Physical Review Letters ◽

10.1103/physrevlett.121.037205 ◽

2018 ◽

Vol 121 (3) ◽

Cited By ~ 10

Author(s):

Daniel D. Scherer ◽

Brian M. Andersen

Keyword(s):

Magnetic Anisotropy ◽

Orbit Coupling ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Iron Based Superconductors ◽

Iron Based

Download Full-text

Atomic-scale control of magnetic anisotropy via novel spin–orbit coupling effect in La2/3Sr1/3MnO3/SrIrO3 superlattices

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1524689113 ◽

2016 ◽

Vol 113 (23) ◽

pp. 6397-6402 ◽

Cited By ~ 46

Author(s):

Di Yi ◽

Jian Liu ◽

Shang-Lin Hsu ◽

Lipeng Zhang ◽

Yongseong Choi ◽

...

Keyword(s):

Magnetic Anisotropy ◽

Transition Metal Oxides ◽

Coupling Effect ◽

Orbit Coupling ◽

Atomic Scale ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Precise Control ◽

Magnetic Easy Axis ◽

Scale Control

Magnetic anisotropy (MA) is one of the most important material properties for modern spintronic devices. Conventional manipulation of the intrinsic MA, i.e., magnetocrystalline anisotropy (MCA), typically depends upon crystal symmetry. Extrinsic control over the MA is usually achieved by introducing shape anisotropy or exchange bias from another magnetically ordered material. Here we demonstrate a pathway to manipulate MA of 3d transition-metal oxides (TMOs) by digitally inserting nonmagnetic 5d TMOs with pronounced spin–orbit coupling (SOC). High-quality superlattices comprising ferromagnetic La2/3Sr1/3MnO3 (LSMO) and paramagnetic SrIrO3 (SIO) are synthesized with the precise control of thickness at the atomic scale. Magnetic easy-axis reorientation is observed by controlling the dimensionality of SIO, mediated through the emergence of a novel spin–orbit state within the nominally paramagnetic SIO.

Download Full-text

Induction of large magnetic anisotropy energy and formation of multiple Dirac states in SrIrO3 films: Role of correlation and spin–orbit coupling

Applied Physics Letters ◽

10.1063/5.0076375 ◽

2021 ◽

Vol 119 (26) ◽

pp. 261906

Author(s):

Amit Chauhan ◽

B. R. K. Nanda

Keyword(s):

Magnetic Anisotropy ◽

Anisotropy Energy ◽

Orbit Coupling ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Magnetic Anisotropy Energy

Download Full-text

Low-Field Magnetic Anisotropy of Sr2IrO4

10.21203/rs.3.rs-831500/v1 ◽

2021 ◽

Author(s):

Muhammad Nauman ◽

Tayyaba Hussain ◽

Joonyoung Choi ◽

Nara Lee ◽

Young Jai Choi ◽

...

Keyword(s):

Magnetic Anisotropy ◽

Exchange Interaction ◽

Exchange Interactions ◽

Orbit Coupling ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Easy Magnetization ◽

Magnetic Exchange ◽

Crystal Field Effect ◽

Out Of Plane

Abstract Magnetic anisotropy in strontium iridate (Sr2IrO4) is essential because of its strong spin-orbit coupling and crystal field effect. In this study, we investigated the detailed mapping of the out-of-plane (OOP) magnetic anisotropy in Sr2IrO4 for different sample orientations using torque magnetometry measurements in the low-magnetic-field region before the isospins are fully ordered. Dominant in-plane anisotropy was identified at low fields, confirming the b axis as an easy magnetization axis. Based on the fitting analysis of the strong uniaxial magnetic anisotropy, we observed that the main anisotropic effect arises from a spin–orbit-coupled magnetic exchange interaction that affects the OOP interaction. The interlayer exchange interaction results in additional anisotropic terms owing to the tilting of the isospins. Our results are relevant for understanding OOP magnetic anisotropy and provide a new way to analyze the effects of spin–orbit-coupling and interlayer magnetic exchange interactions. This study provides a new insight into the understanding of bulk magnetic, magneto-transport, and spintronic behavior of Sr2IrO4 for future studies.

Download Full-text

Orbital moment probed spin orbit coupling effects on anisotropy and damping in CoFeB thin films

RSC Advances ◽

10.1039/c6ra19837f ◽

2016 ◽

Vol 6 (97) ◽

pp. 94717-94722 ◽

Cited By ~ 9

Author(s):

Deepika Jhajhria ◽

Dinesh K. Pandya ◽

Sujeet Chaudhary

Keyword(s):

Thin Films ◽

Magnetic Anisotropy ◽

Orbit Coupling ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Coupling Effects ◽

Orbital Moment ◽

Stress Variations

Spin orbit coupling based direct correlation between magnetic anisotropy and damping is established in CoFeB thin films on compositional and stress variations.

Download Full-text

Perpendicular Magnetic Anisotropy on W-based Spin-Orbit Torque CoFeB | MgO MRAM Stacks

MRS Proceedings ◽

10.1557/opl.2015.191 ◽

2015 ◽

Vol 1729 ◽

pp. 73-78 ◽

Cited By ~ 2

Author(s):

Andreas Kaidatzis ◽

Vasileios Psycharis ◽

José Miguel García-Martín ◽

Cristina Bran ◽

Manuel Vázquez ◽

...

Keyword(s):

Magnetic Anisotropy ◽

Layer Thickness ◽

High Spin ◽

Perpendicular Magnetic Anisotropy ◽

Orbit Coupling ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Β Phase

ABSTRACTWe study W | Ta | CoFeB | MgO stacks for spin-orbit torque MRAM applications. A strong perpendicular magnetic anisotropy is obtained after annealing for CoFeB layer thickness of 0.9 nm or 1.2 nm and for specific W/Ta ratios, were the Ta layer thickness is between 0.3 nm and 1 nm. Furthermore, the desired high-spin orbit coupling β-phase of W is preserved even after annealing at 350°C. We argue that an efficient B getter, like Ta, is necessary for the coherent crystallization of the CoFeB | MgO interface that allows for the establishment of perpendicular magnetic anisotropy.

Download Full-text