通过场依赖的X射线共振磁性散射在多层中探测三维自旋纹理
Erick Burgos-Parra1,2,3, Yanis Sassi4, William Legrand4
1Synchrotron SOLEIL, L'Orme des Merisiers, 91192, Gif-sur-Yvette, France. erick.burgos@usach.cl.
Scientific reports
|July 20, 2023
概括
研究人员使用X射线共振磁散射在薄膜中观察到复杂的磁域壁. 这项技术精确地绘制了3D磁纹,揭示了混合的Neil-Bloch壁结构.
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
- 磁力学 磁力学 是一种
背景情况:
- 具有垂直异构的磁性薄膜表现出复杂的域壁结构.
- 混合域墙,以不同层的 Néel 墙和 Bloch 墙为特色,在理论上可以预测,但在实验上难以观察.
- 磁化的三维特征对于理解这些结构至关重要.
研究的目的:
- 实验性地研究和描述混合域墙壁在磁性多层中的三维磁性纹理.
- 使用X射线共振磁性散射 (XRMS) 与圆形二重化对比进行详细分析.
- 推进XRMS方法论用于对外平面磁性结构的定量评估.
主要方法:
- 在磁性多层上测量场依赖的X射线共振磁性散射.
- 利用圆形二重化对比度用于敏感的磁探测.
- 实验XRMS数据与微磁模拟的结合.
- 开发一种新的校准方法,使用非布拉格角度测量进行定量分析.
主要成果:
- 成功描述了混合域墙壁的三维磁纹.
- 在混合结构中确定布洛赫墙壁组件的大小和位置的厚度解析.
- 通过先进的XRMS方法,对外平面磁性结构进行定量评估.
结论:
- 这项研究证实了混合域壁在磁多层中的存在,并提供了详细的描述.
- 开发的XRMS方法为定量3D磁结构分析提供了一个强大的工具.
- 这种方法可以扩展到研究其他性磁性结构,如skyrmions和磁性bobbers.
相关概念视频
01:05Atomic Nuclei: Magnetic Resonance
688
The number of nuclear spins aligned in the lower energy state is slightly greater than those in the higher energy state. In the presence of an external magnetic field, as the spins precess at the Larmor frequency, the excess population results in a net magnetization oriented along the z axis. When a pulse or a short burst of radio waves at the Larmor frequency is applied along the x axis, the coupling of frequencies causes resonance and flips the nuclear spins of the excess population from the...
688
01:14NMR Spectrometers: Resolution and Error Correction
727
When magnetic nuclei in a sample achieve resonance and undergo relaxation, the signal detected in NMR is an approximately exponential free induction decay. Fourier transform of an exponential decay yields a Lorentzian peak in the frequency domain. Lorentzian peaks in an NMR spectrum are defined by their amplitude, full width at half maximum, and position, where the peak width is governed by the spin-spin relaxation time alone. In real experiments, however, the applied magnetic field is rendered...
727
01:12Double Resonance Techniques: Overview
247
Double resonance techniques in Nuclear Magnetic Resonance (NMR) spectroscopy involve the simultaneous application of two different frequencies or radiofrequency pulses to manipulate and observe two distinct nuclear spins. One important application of double resonance is spin decoupling, which selectively suppresses coupling with one type of nucleus while observing the NMR signal from another nucleus, simplifying the spectrum and enhancing resolution.
Spin decoupling is usually achieved by...
Spin decoupling is usually achieved by...
247
01:08NMR Spectroscopy: Spin–Spin Coupling
1.5K
The spin state of an NMR-active nucleus can have a slight effect on its immediate electronic environment. This effect propagates through the intervening bonds and affects the electronic environments of NMR-active nuclei up to three bonds away; occasionally, even farther. This phenomenon is called spin–spin coupling or J-coupling. Coupling interactions are mutual and result in small changes in the absorption frequencies of both nuclei involved. While nuclei of the same element are involved...
1.5K
01:03Atomic Nuclei: Nuclear Spin State Overview
1.0K
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...
1.0K
01:23Atomic Nuclei: Nuclear Relaxation Processes
682
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.
682