在扭曲的双层NiI_{2}中引发Moiré的磁电
Haiyan Zhu1, Hongyu Yu1, Weiqin Zhu1
1Fudan University, Key Laboratory of Computational Physical Sciences (Ministry of Education), Institute of Computational Physical Sciences, State Key Laboratory of Surface Physics, and Department of Physics, Shanghai 200433, China.
Physical review letters
|November 21, 2025
概括
扭曲的磁性材料表现出由于晶格放松而具有可调节的多铁性质. 这项研究揭示了扭曲双层NiI2中的合作离子和自旋驱动铁电,这对于新型多铁器件至关重要.
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
- 计算物理 计算物理
背景情况:
- 扭曲的范德瓦尔斯材料对多铁工程具有前景.
- 在这些材料中模拟大规模的莫雷超级格子提出了重大挑战.
研究的目的:
- 开发和应用机器学习潜力,用于模拟扭曲双层NiI2.2中的自旋格合系统.
- 调查多铁素性质的出现,包括旋转驱动的极化和铁电,作为扭曲角度和晶格放松的函数.
主要方法:
- 使用SpinGNN++框架开发一个全面的原子间机器学习潜力.
- 将潜力应用于扭曲的双层NiI2,包括结构放松.
- 整合了 Katsura-Nagaosa-Balatsky 通用机制,用于精确的旋转驱动偏振计算.
主要成果:
- 结构松会诱导层间间距和离子转移中的莫雷周期调节.
- 机器学习潜力准确地捕获磁性配置和旋转相互作用.
- 在1.89°和2.45°之间的扭转角度观察到合作的离子和自旋驱动的铁电,产生丰富的极化纹理.
- 格子放松对于产生极磁拓学,如 skyrmions,至关重要.
- 在接近60°的扭转角度,堆叠依赖的铁电位移导致极性meron-antimeron网络.
结论:
- 扭曲的双层NiI2表现出合作的离子和自旋驱动的铁电.
- 格子放松在这些系统中起到关键作用,使多铁体现象成为可能.
- 扭曲的范德瓦尔斯磁铁作为可适应的平台,用于开发可调节的多铁子装置.
相关概念视频
01:23Magnetic Field due to Moving Charges
11.4K
A stationary charge creates and interacts with the electric field, while a moving charge creates a magnetic field.
Consider a point charge moving with a constant velocity. Like the electric field, the magnetic field at any point is directly proportional to the magnitude of the charge and inversely proportional to the square of the distance between the source point and the field point. However, unlike the electric field, the magnetic field is always perpendicular to the plane containing the line...
Consider a point charge moving with a constant velocity. Like the electric field, the magnetic field at any point is directly proportional to the magnitude of the charge and inversely proportional to the square of the distance between the source point and the field point. However, unlike the electric field, the magnetic field is always perpendicular to the plane containing the line...
11.4K
01:28Magnetic Field Due To A Thin Straight Wire
6.0K
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.
6.0K
01:24Potential Due to a Magnetized Object
754
Magnetic dipoles in magnetic materials are aligned when placed under an external magnetic field. For paramagnets and ferromagnets, dipole alignment occurs in the direction of the magnetic field. However, the dipoles align opposite to the field in the case of diamagnets. This state of magnetic polarization due to the external field is called magnetization. Magnetization is defined as the dipole moment per unit volume. It plays a similar role to polarization in electrostatics.
The vector...
The vector...
754
01:31Ferromagnetism
2.9K
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...
2.9K
01:13Magnetic Force Between Two Parallel Currents
4.5K
Two long, straight, and parallel current-carrying conductors exert a force of equal magnitude on one another. The direction of the force depends on the current direction in the conductors.
The force exerted by the magnetic field due to the first conductor over a finite length of the second conductor is given as the product of the current in the second conductor and the vector product of the length vector along the current element and the field due to the first conductor. According to the...
The force exerted by the magnetic field due to the first conductor over a finite length of the second conductor is given as the product of the current in the second conductor and the vector product of the length vector along the current element and the field due to the first conductor. According to the...
4.5K
01:18Magnetic Field Due to Two Straight Wires
4.4K
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.
4.4K