在合成反铁磁铁中,通过双旋转轨道扭矩有效操纵磁域壁
Hiroto Masuda1, Yuta Yamane2,3, Takaaki Dohi3,4
1Institute for Materials Research, Tohoku University, Sendai, 980-8577, Japan.
Advanced science (Weinheim, Baden-Wurttemberg, Germany)
|October 17, 2025
概括
在合成反铁磁体中,电流诱导的域壁运动对于先进的记忆器件至关重要. 这项研究表明,有效的域壁运动使用双旋转轨道扭矩,通过反对称的层间交换合增强.
科学领域:
- 这就是Spintronics.
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
背景情况:
- 电流诱导的域壁运动 (CIDWM) 对高密度磁性记忆至关重要.
- 合成反铁磁体为快速操作的设备提供了潜力.
研究的目的:
- 在Pt/Co/Ir/Co/Pt合成反铁磁体结构中研究CIDWM.
- 探索双旋转轨道扭矩 (SOT) 和反对称层间交换合 (AIEC) 对CIDWM的影响.
主要方法:
- 制造一个Pt/Co/Ir/Co/Pt多层结构.
- 在 Pt 层中通过旋转霍尔效应产生的自旋电流的应用.
- 在应用电流密度下分析域壁核和运动.
主要成果:
- 从顶部和底部Pt层的双SOT有效地核化反向磁域,并驱动CIDWM.
- 在~10^11 A m^-2.的电流密度下,可以实现CIDWM.
- 观察到AIEC大小和域壁速度之间的正相关性.
- 发现AIEC大小与域核形成所需的电流密度之间存在负相关性.
结论:
- 双 SOT 机制克服了预期的取消,使有效的 CIDWM.
- 反对称的间层交换合提高了CIDWM的性能.
- 本文介绍了使用合成反铁磁铁设计SOT域壁设备的新策略.
相关概念视频
Ferromagnetism
3.0K
Materials like iron, nickel, and cobalt consist of magnetic domains, within which the magnetic dipoles are arranged parallel to each other. The magnetic dipoles are rigidly aligned in the same direction within a domain by quantum mechanical coupling among the atoms. This coupling is so strong that even thermal agitation at room temperature cannot break it. The result is that each domain has a net dipole moment. However, some materials have weaker coupling, and are ferromagnetic at lower...
3.0K
Diamagnetism
2.9K
Materials consisting of paired electrons have zero net magnetic moments. However, when these materials are placed under an external magnetic field, the moments opposite to the field are induced. Such materials are called diamagnets. Diamagnetism is the response of the diamagnets when placed in an external magnetic field.
Diamagnetism was discovered by Anton Brugmans in 1778 when he observed that bismuth gets repelled by magnetic fields, thus theorizing that diamagnets get repelled by magnets....
Diamagnetism was discovered by Anton Brugmans in 1778 when he observed that bismuth gets repelled by magnetic fields, thus theorizing that diamagnets get repelled by magnets....
2.9K
Valence Bond Theory
11.2K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
11.2K
Atomic Nuclei: Nuclear Spin State Overview
1.9K
NMR-active nuclei have energy levels called 'spin states' that are associated with the orientations of their nuclear magnetic moments. In the absence of a magnetic field, the nuclear magnetic moments are randomly oriented, and the spin states are degenerate. When an external magnetic field is applied, the spin states have only 2 + 1 orientations available to them. A proton with = ½ has two available orientations. Similarly, for a quadrupolar nucleus with a nuclear spin value of one, the...
1.9K
Paramagnetism
3.0K
Paramagnets are materials with unpaired electrons that possess a finite magnetic moment. In the absence of a magnetic field, these moments are randomly oriented, and thus the net moment is zero. Under an external field, a torque acting on the moments tends to align them along the field's direction. However, the random thermal motion of electrons produces a torque opposite to the external field and tries to disorient the moments. These two competing effects align only a few moments along the...
3.0K
Atomic Nuclei: Nuclear Relaxation Processes
1.2K
In the absence of an external magnetic field, nuclear spin states are degenerate and randomly oriented. When a magnetic field is applied, the spins begin to precess and orient themselves along (lower energy) or against (higher energy) the direction of the field. At equilibrium, a slight excess population of spins exists in the lower energy state. Because the direction of the magnetic field is fixed as the z-axis, the precessing magnetic moments are randomly oriented around the z-axis.
1.2K


