通过它们在极磁体中的六边形到正方形晶体转变,在不同的混合 skyrmion 纹理之间进行过渡
Deepak Singh1, Yukako Fujishiro2, Satoru Hayami3
1Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institute (PSI), CH-5232, Villigen, Switzerland. deepak.singh@psi.ch.
Nature communications
|December 5, 2023
概括
研究人员在EuNiGe3中发现了新的混合磁性 skyrmion 阶段,在六边形和方形晶体结构之间呈现直接过渡. 这一发现推动了对纳米技术的新型拓磁性材料的研究.
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
- 纳米技术纳米技术
背景情况:
- 磁性 skyrmions 是具有纳米技术潜力的拓旋转纹理.
- 斯基尔米恩通常形成六角格子,具有布洛赫或尼尔类型的纹理.
- 在理论上提出了skyrmion阶段之间的直接过渡,但在实验上却很少见.
研究的目的:
- 实验性地研究不同 skyrmion 晶体结构和内部纹理之间的直接过渡.
- 探索极磁体在发现新型拓磁相方面的潜力.
主要方法:
- 在极四角磁铁EuNiGe3.3中实验发现混合斯基米安相.
- 磁场变化以诱导 skyrmion 阶段之间的过渡.
- 理论建模结合动量解析的鲁德曼-基特尔-卡苏亚-约西达和Dzyaloshinskii-Moriya相互作用.
主要成果:
- 在EuNiGe3中,有两种不同的杂交 skyrmion 阶段,其内部有异性质的Bloch 和 Néel 结构.
- 在这两个混合相之间观察到由磁场驱动的直接过渡.
- 这种转变涉及从六边形到正方形 skyrmion 晶格的同时转变.
结论:
- 具有复杂相互作用的极磁体对发现新的拓磁相具有前景.
- 观察到的现象验证了关于 skyrmion 阶段过渡和格子转换的理论.
- 这项工作为设计使用可调节的 skyrmion 纹理的先进自旋电子设备开辟了新的途径.
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