磁绝缘介质/半导体合金(Bi:TmIG/GeBi)自旋异质结薄膜及新效应研究

Electron spin has been injected and transmitted in ferrite insulation medium, heavy metal or semiconductor film interface by wave form, in order to form quantum logic and detection device. Electron spin wave not only can directly process signals in micronwave/milimeter wave range, but also can lower 2-3 orders of magnitude of the loss, which will be one of the backing materials in modern microwave integration system and quantum communication in future. This project first propose to dope Bismuth in TmIG (rare earth garnet) film to construct spin heterojunction and anomalous spin Hall effect with upper GeBi film. The epitaxial growth Bi:TmIG film which has perpendicular magnetic moment, and the Ge1-xBix which has low dislocation density, can constitute a spin shadow junction in nanoscale . Explore the Bi:TmIG/GeBi interface spin injection enhancement mechanism, discover the anomalous spin Hall effect, film elements and the rule between Bi ion subtitute and semiconductor doping. Fabricating spin Hall logic device, measuring the Polar Kerr effect and anomalous spin Hall effect will lay the foundation of device and system applications.

电子自旋以波动形式在铁氧体绝缘介质与重金属或半导体薄膜界面注入与传输，形成自旋波量子逻辑器件和传感探测器件，它不仅可以在微波/毫米波段直接信号处理，而且可将损耗降减2-3个数量级，因而成为现代微波系统集成和未来量子通信的支撑材料之一。本项目首次提出掺Bi的TmIG薄膜稀土石榴石薄膜与半导体GeBi薄膜构建自旋异质结材料及反常自旋霍尔效应的思想。外延生长具有垂直于膜面磁矩分布的Bi:TmIG薄膜与低位错密度的半导体Ge1-xBix合金薄膜，并构成纳米级自旋浅结，探索这一界面自旋电子注入增强机制，发现其反常自旋霍尔效应与薄膜成分，Bi离子替代与半导体掺杂等之间的规律，制备自旋薄膜霍尔逻辑器件，测试其极向克尔效应和反常自旋霍尔效应，为器件及系统应用打下材料基础。

本项目首次提出使用掺Bi的TmIG稀土石榴石薄膜与半导体GeBi薄膜构建自旋异质结材料及产生反常自旋霍尔效应的思想，外延生长具有垂直于膜面磁矩分布的Bi:TmIG薄膜与低位错密度的半导体Ge1-xBix合金薄膜，并制备构成纳米级自旋浅结，探索这一界面自旋-轨道作用场与增强自旋霍尔效应的关系，减小驱动电流密度的途径，确定不同异质结磁开关翻转场的大小。同时，通过利用高自旋极化率的Bi离子，用它进行离子替代与半导体掺杂，制备Bi:TmIG/Ge1-xBix相关自旋薄膜霍尔逻辑器件。测试其极向克尔效应和反常自旋霍尔效应，动态证明电驱动自旋磁矩翻转开关效应与Bi:TmIG薄膜之间性能之关系。且测试发现，在同样厚度情况下，Bi:TmIG/GeBi自旋异质结的所需的异常霍尔翻转场相较于Bi:TmIG/Pt缩小近一半，为未来微波集成、量子探测与传感、逻辑处理器件打下材料基础。