在金属反铁磁铁中长寿命的自旋波
G Poelchen1,2,3, J Hellwig4, M Peters4
1European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043, Grenoble, France. georg.poelchen@esrf.fr.
Nature communications
|September 5, 2023
概括
像CeCo2P2这样的金属反铁磁体是长寿命磁体的宿主,对于节能旋转磁器件至关重要. 这一发现克服了传统金属的局限性,为太赫兹 (THz) 磁应用提供了新的可能性.
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
- 这就是Spintronics.
背景情况:
- 集体自旋激发,磁子 (或自旋波),是低能自旋电子器件的关键.
- 由于与Stoner连续体的强合,金属中的Magnon寿命通常很短,这限制了它们的使用.
- 对于可检测的自旋流,需要具有长寿命的高频磁子.
研究的目的:
- 为了研究金属反铁磁体在容纳长寿命磁子方面的潜力.
- 为了确定适用于具有超低能耗的新型自旋电子设备的材料.
- 了解金属系统中控制磁寿命的因素.
主要方法:
- 预测马格农行为的第一原则计算.
- 响应无弹性X射线散射 (RIXS) 测量用于实验验证.
- 使用同结构化合物的比较研究 (CeCo2P2与LaCo2P2).
主要成果:
- 在太赫兹 (THz) 模式下,CeCo2P2表现出长寿命的磁子.
- 计算和RIXS证实了CeCo2P2.2中低能旋转翻转石头激发的抑制.
- CeCo2P2和LaCo2P2之间的结构和电子差异解释了磁阻尼的变化.
结论:
- 长寿命的THz磁子可以存在于散装金属系统中,这挑战了以前的假设.
- CeCo2P2 作为一种模型系统,用于金属中未缩的 THz 磁激发.
- 这项工作为发现新的金属磁系统为先进的自旋电子学提供了一条途径.
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