在使用自然光的合成反铁磁体中,确定性磁化逆转
Yujing Du1, Yifan Zhao1, Lei Wang2
1Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education & International Center for Dielectric Research, School of Electronic Science and Engineering, State Key Laboratory for Manufacturing Systems Engineering, The International Joint Laboratory for Micro/Nano Manufacturing and Measurement Technology, Xi'an Jiaotong University, Xi'an, 710049, China.
Small (Weinheim an der Bergstrasse, Germany)
|July 5, 2023
概括
可见光现在可以控制自旋电子设备中的磁性,使反铁磁和铁磁状态之间的可逆切换成为可能. 这一创新承诺节能太阳能驱动的记忆,提高可靠性和速度.
科学领域:
- 这就是Spintronics.
- 材料科学 材料科学 材料科学
- 光子学 是一个光子学.
背景情况:
- 传统的自旋电子面临着诸如供暖和能源消耗等局限性.
- 现有的电压驱动方法遭受了接口腐蚀.
- 为了节能和可靠的自旋电子,需要调整铁磁的新方法.
研究的目的:
- 为了证明界面交换相互作用的可见光控制.
- 使用光来实现反铁磁 (AFM) 和铁磁 (FM) 状态之间的可逆切换.
- 开发节能和可靠的自旋电子设备.
主要方法:
- 用可见光将光电子合到使用可见光的CoFeB/Cu/CoFeB/PN Si异构中.
- 磁光克尔效应测量用于分析域切换.
- 第一个原则计算,以了解底层机制.
- 制造了一种可见光控制装置的原型.
主要成果:
- 在可见光下,在AFM和FM状态之间完全和可逆地切换.
- 通过可见光和一个小的磁偏差场控制的决定性180°磁化开关.
- 经过证明的光电子兴奋剂通过提高费米能量来增加交换相互作用.
- 一个原型设备显示了0.35%的巨型磁电阻比率变化,用于两种状态的切换.
结论:
- 可见光可以有效地调整合成反铁磁异构结构中的界面交换相互作用.
- 这种以光驱动的方法为快速,紧和节能的太阳能驱动存储器设备提供了途径.
- 这些发现克服了电流驱动和电压驱动的自旋电子技术的局限性.
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