在FM/AFM双层中使用THz频率脉冲对磁化逆转的模拟
Joel Hirst1, Sergiu Ruta2,3, Jerome Jackson4
1Materials & Engineering Research Institute, Sheffield Hallam University, Howard Street, Sheffield, S1 1WB, UK. joel.hirst@student.shu.ac.uk.
Scientific reports
|July 28, 2023
概括
抗铁磁铁 (AFM) 可以使用太赫兹 (THz) 脉冲切换,从而实现数据存储的超快速控制. 将AFM与铁磁铁 (FM) 合起来,可以有效地读取AFM.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 这就是Spintronics.
- 材料科学 材料科学 材料科学
背景情况:
- 反铁磁铁 (AFM) 为超快的应用提供特拉赫兹 (THz) 范围的高频响应.
- 读取AFM的磁性状态是具有挑战性的,因为它取消了亚晶格磁化.
- 将AFM连接到铁磁铁 (FM) 提供了一种可行的方法,可以通过磁阻检测状态.
研究的目的:
- 从理论上建模并确定使用THz脉冲在AFM/FM双层中切换AFM磁化条件.
- 探索接口合和FM层厚度对开关动态的影响.
- 为了证明潜在的数据存储应用程序的强大和可控制的磁化切换.
主要方法:
- 在THz频率脉冲下对AFM/FM双层动态的理论建模.
- 阶段图分析以确定最佳切换条件.
- 研究物质前置和THz场所影响的逆转路径.
主要成果:
- 识别了切换AFM磁化与中度THz场幅度和短脉冲持续时间的条件.
- 经过证明的一致切换,增加了接口合和FM层厚度.
- 观察到由合前置和THz诱导的场所产生的多种反转路径.
- AFM驱动开关,通过交换合在FM层中诱导更高频率的动态.
结论:
- THz脉冲可以有效地切换AFM磁化在AFM/FM双层.
- 开关机制在设备相关的广泛温度范围内是稳固的.
- 这种方法为下一代超高速数据存储和处理提供了有希望的途径.
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