在铁磁维尔半金属,Co2MnGa中具有90°扭转的无otropic电阻
Nicholas P Quirk1, Guangming Cheng2, Kaustuv Manna3
1Department of Physics, Princeton University, Princeton, NJ, 08544, USA.
Nature communications
|October 18, 2023
概括
研究人员在超薄铁磁维尔半金属Co2MnGa晶体中发现了一种独特的90度阻力扭曲. 这种异构性表明表面状态与散装状态是分离的,这是凝聚物质物理学的新发现.
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
- 拓学材料 拓学材料
背景情况:
- 韦尔半金属具有独特的电子性质,如奇拉异常和韦尔轨道.
- 拓保护的表面状态是韦尔半金属的关键特征.
研究的目的:
- 研究铁磁维尔半金属Co2MnGa的运输特性.
- 在微米厚的Co2MnGa晶体中探索独特的现象.
主要方法:
- 聚焦离子束研磨以创建微米厚的晶体.
- 测量平面电阻的异构性.
- 对称性分析和静电模拟.
主要成果:
- Co2MnGa晶体表现出很大的平面电阻异构性 (10x).
- 在相反的晶体面之间旋转90度的电阻异构轴.
- 模拟表明,表面状态受到大规模杂交的阻碍.
结论:
- 在超薄的Co2MnGa中观察到的异质性模仿了具有孤立表面状态的同质导体.
- 90度的扭转表明了一种新的表面电子结构.
- 需要进一步的实验来确认这些表面状态的起源.
相关概念视频
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
Magnetic Field Due to Two Straight Wires
2.6K
Consider two parallel straight wires carrying a current of 10 A and 20 A in the same direction and separated by a distance of 20 cm. Calculate the magnetic field at a point "P2", midway between the wires. Also, evaluate the magnetic field when the direction of the current is reversed in the second wire.
2.6K
Magnetic Field Due To A Thin Straight Wire
4.9K
Consider an infinitely long straight wire carrying a current I. The magnetic field at point P at a distance a from the origin can be calculated using the Biot-Savart law.
4.9K
Magnetic Susceptibility and Permeability
1.1K
In linear magnetic materials, like paramagnets and diamagnets, magnetization is proportional to the magnetic field intensity. The constant of proportionality, a dimensionless number, is called magnetic susceptibility. The value of the susceptibility depends on the type of material.
When diamagnetic materials are placed under an external magnetic field, the moments opposite to the field are induced. Hence, the susceptibility for diamagnets has a minimal negative value of 10-5–10-6. Since...
When diamagnetic materials are placed under an external magnetic field, the moments opposite to the field are induced. Hence, the susceptibility for diamagnets has a minimal negative value of 10-5–10-6. Since...
1.1K
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
Biasing of Metal-Semiconductor Junctions
261
Biasing metal-semiconductor junctions involves applying a voltage across the junction. Specifically, the metal is connected to a voltage source, while the semiconductor is grounded. This technique is essential for controlling the direction and magnitude of current flow in electronic devices, including diodes, transistors, and photovoltaic cells.
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
261


