旋转扭矩驱动的反铁磁共振是一种反铁磁共振
Yongjian Zhou1, Tingwen Guo1,2, Lei Han1
1Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering, Tsinghua University, Beijing 100084, P. R. China.
Science advances
|January 12, 2024
概括
研究人员在室温下实现了旋转扭矩驱动的反铁磁共振 (ST-AFMR). 这一突破使尼尔向量的控制和检测成为可能,为更快的反铁磁自旋电子设备铺平了道路.
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:
- 反铁磁螺旋电子技术提供了高速数据处理的潜力,因为其内在的快速动态.
- 超快自旋电流对于访问和理解反铁磁自旋动力学至关重要.
- 旋转扭矩驱动的反铁磁共振 (ST-AFMR) 对于实际应用是可取的,但在 Néel 矢量控制和检测方面存在挑战.
研究的目的:
- 在材料系统中实验观察和描述旋转扭矩驱动的反铁磁共振 (ST-AFMR).
- 通过ST-AFMR来证明Neel载体的控制和检测.
- 探索ST-AFMR在开发先进反铁磁自旋电子装置方面的潜力.
主要方法:
- 在室温下在Y3Fe5O12/α-Fe2O3/Pt异构中对ST-AFMR的实验观察.
- 利用反铁磁负旋转的霍尔磁阻诱导的旋转纠正效应用于信号生成.
- 采用微磁模拟来分析尼尔向量的共振行为和倾斜的时刻.
主要成果:
- 在Y3Fe5O12/α-Fe2O3/Pt系统中成功观察了ST-AFMR.
- 与铁磁铁相比,证明了Néel向量的振荡有助于产生具有相反标志的可测量的电压信号.
- 在α-Fe2O3的尼尔向量和Y3Fe5O12缓冲层的磁化之间建立了强大的合,以方便控制.
- 微磁模拟证实了Neel向量的圆共振和α-Fe2O3.3中的斜矩.
结论:
- 这项研究证明了ST-AFMR在室温下的可行性,克服了以前的局限性.
- 这些发现突出了反铁磁铁在发电信号的反铁磁铁中旋转纠正效应的作用.
- 这项工作代表了向电控反铁磁太赫兹发射器和先进的自旋电子设备迈出的重要一步.
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