巨型域墙异常霍尔效应在一个分层的反铁磁体EuAl_{2}Si_{2}中
Wei Xia1,2, Bo Bai1, Xuejiao Chen3
1School of Physical Science and Technology, <a href="https://ror.org/030bhh786">ShanghaiTech University</a>, Shanghai 201210, China.
Physical review letters
|December 6, 2024
概括
在反铁磁体中发现了异常霍尔效应 (AHE) 的新起源,由域壁斜散射驱动. 这一发现揭示了实现大型AHE的新途径,这对于自旋电子设备应用至关重要.
科学领域:
- 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
- 这就是Spintronics.
背景情况:
- 无散射的霍尔效应通常需要时间逆转对称性破坏 (TRSB).
- 异常霍尔效应 (AHE) 通常与自发磁化有关,使其在反铁磁体中意想不到.
- 最近的研究发现,由于非对线性旋转结构和果曲率,在特定的反铁磁体中观察到很大的AHE.
研究的目的:
- 在分层反铁磁体中研究AHE的新机制.
- 通过实验证明域壁 (DW) 斜散射在生成AHE中的作用.
- 为了探索这种现象对自旋电子设备的潜力.
主要方法:
- 对分层反铁磁体EuAl2Si2.2.进行实验调查.
- 域壁结构的特征及其对外部磁场的反应.
- 测量霍尔导电性,专注于域墙霍尔导电性 (DWHC).
主要成果:
- 发现了一种新的AHE机制,源于涉及韦尔点的域壁 (DW) 斜散射.
- EuAl2Si2 呈现出独特的,磁性调节的周期条纹域壁结构.
- 创纪录的DWHC达到了~1.51x10^4 S/cm,明显超过了内在的AHE.
结论:
- 域壁斜散射为在反铁磁体中实现大型异常霍尔效应提供了一个新的范式.
- 在EuAl2Si2中可调节域壁结构为先进的旋转电子应用提供了潜力.
- 这一发现挑战了对磁性材料中AHE机制的现有理解.
相关概念视频
The Hall Effect
2.2K
Edwin H. Hall, in the year 1879, devised an experiment that could be used to identify the polarity of the predominant charge carriers in a conducting material. From a historical perspective, this experiment was the first to demonstrate that the charge carriers in most metals are negative.
2.2K
Ferromagnetism
2.4K
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...
2.4K
Magnetostatic Boundary Conditions
874
An electric field suffers a discontinuity at a surface charge. Similarly, a magnetic field is discontinuous at a surface current. The perpendicular component of a magnetic field is continuous across the interface of two magnetic mediums. In contrast, its parallel component, perpendicular to the current, is discontinuous by the amount equal to the product of the vacuum permeability and the surface current. Like the scalar potential in electrostatics, the vector potential is also continuous...
874
Metallic Solids
18.2K
Metallic solids such as crystals of copper, aluminum, and iron are formed by metal atoms. The structure of metallic crystals is often described as a uniform distribution of atomic nuclei within a “sea” of delocalized electrons. The atoms within such a metallic solid are held together by a unique force known as metallic bonding that gives rise to many useful and varied bulk properties.
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability....
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability....
18.2K
Diamagnetism
2.4K
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....
2.4K
Ionic Crystal Structures
14.1K
Ionic crystals consist of two or more different kinds of ions that usually have different sizes. The packing of these ions into a crystal structure is more complex than the packing of metal atoms that are the same size.
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
14.1K


