通过在非均的Dzyaloshinskii-Moriya相互作用的存在下分散的反铁磁旋波放大
Taeheon Kim1, Geun-Ju Kim1, Jung-Il Kim1
1Electro-Medical Equipment Research Division, Applied Electromagnetic Wave Research Center, Korea Electrotechnology Research Institute, Ansan 15588, Republic of Korea.
Materials (Basel, Switzerland)
|November 27, 2024
概括
我们提出了一种方法,使用非均的Dzyaloshinskii-Moriya (DM) 相互作用来放大反铁磁体 (AFM) 中的自旋波 (SW). 这种技术使得共振放大和潜在的应用在低分散的磁装置.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 这就是Spintronics.
- 马格尼尼克斯公司 (Magnonics)
背景情况:
- 旋转波 (SW) 是磁性材料中的基本激发.
- 抗铁磁体 (AFM) 为低散射的磁铁器件提供了潜力.
- 控制SW传播和放大对于设备应用至关重要.
研究的目的:
- 提出并从理论上研究一种在隔热反铁磁体中放大自旋波的方法.
- 探索非均的Dzyaloshinskii-Moriya (DM) 相互作用在旋波放大中的作用.
- 为了证明基于这种放大机制创建自旋波晶体管和整流器的潜力.
主要方法:
- 在AFM中旋波传播的理论建模与工程DM相互作用.
- 使用非均的DM相互作用来创建共振腔.
- 使用转移矩阵方法对SW散射和放大进行数值模拟.
主要成果:
- 不统一的DM相互作用会产生潜在的屏障,形成SWs的共振腔.
- 在相反的性SW之间散射会在相匹配条件下导致共振放大.
- 电场诱导的DM相互作用和伪二极异极性扩大SW频段,使多个共振模式成为可能.
- 数字模拟证实了SW散射对放大功率的显著贡献.
结论:
- 拟议的方法允许在隔热AFM中有效放大旋波.
- 开发的方法有助于创建自旋波晶体管和整流器.
- 这项研究有助于开发基于AFM的先进绝缘磁设备,以最小化的焦耳加热.
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