在软磁盖阵列中的磁性状态的尺寸依赖的可比性
Shan Abraham Sam1, Johannes Seyd2, Aladin Ullrich2
1Department of Physics, Cochin University of Science and Technology, Cochin 682022, India.
Nanotechnology
|March 11, 2024
概括
研究人员探索了磁盖结构,发现大小和厚度控制了状态转换的能量屏障. 这允许在特定温度下调整磁位稳定性和无hysteresis的切换.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 纳米技术纳米技术
背景情况:
- 密集的磁盖结构阵列可以容纳磁.
- 了解磁态转换对于数据存储应用至关重要.
研究的目的:
- 研究磁盖结构中的尺寸依赖的能量障碍.
- 通过控制帽子尺寸来调整磁性双稳定性和切换行为.
主要方法:
- 在聚乙烯球体阵列上制造软磁薄膜.
- 分析磁场辅助的在线和状状态之间的切换.
- 两叉温度的确定及其对帽子几何学的依赖.
主要成果:
- 状态转换的能量屏障可以通过盖子直径和厚度进行调节.
- 在分叉温度下观察到无歇斯底里切换.
- 分叉温度随着盖子直径 (固定的厚度) 的增加而降低.
- 分裂温度随着薄膜厚度 (固定直径) 的增加而增加.
结论:
- 磁静电能是控制能量障碍和磁性双稳定性的关键因素.
- 定制帽子尺寸提供了一种精确控制磁切换行为的方法.
- 在量身定制的纳米结构中,证明了无歇斯底里磁性双稳定性的潜力.
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
Paramagnetism
2.5K
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...
2.5K
Atomic Nuclei: Nuclear Spin State Overview
943
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...
943
Atomic Nuclei: Nuclear Relaxation Processes
654
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.
654
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
Colors and Magnetism
11.7K
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
11.7K


