Reflection-based Spintronics

这项研究的目的是设计基于动态磁邻近效应的薄膜自旋电子器件。在非磁性材料中，传导电子从绝缘性磁性材料的界面反射而产生的自旋极化是非零的。该方法是完全原位制备非磁性导体/磁绝缘体结构，然后通过三种互补技术：隧道磁阻、隧道自旋极化和x射线磁圆二向色性来探测所产生的自旋极化电流。还将探索具有独立可寻址磁层的三层器件结构。智能优点：该项目可能引领全电子自旋电子学的范式转变。目前的努力集中在将铁磁体中的自旋注入非磁性材料上。然而，自旋注入阻碍了进展，特别是在基于半导体的器件方面。所提出的器件通过从绝缘磁栅上反射来在非磁性传导通道中产生自旋极化，从而避免了注入的困难。该项目将开发一系列更复杂的设备架构的构建块，能够提供电可调的自旋极化电流。广泛的影响：这项变革性的研究可能会简化自旋电子学与现有后端半导体工艺的集成，从而大幅降低商业自旋电子学的障碍。该计划通过统一物理、工程和材料概念，并通过为高中和本科实验室开发动手操作的自旋电子学实验，整合了对本科生和研究生的教学和多学科培训，包括那些来自代表不足的群体的学生。这项工作通过南佛罗里达大学和高级光源公司之间的一项新合作来增强基础设施。

The objective of this research is to engineer thin film spintronic devices based on a dynamic magnetic proximity effect. A non-zero spin-polarization will be induced in a non-magnetic material by reflection of conduction electrons off the interface of an insulating magnetic material. The approach is to fabricate non-magnetic-conductor/magnetic-insulator structures completely in situ, then probe the resulting spin-polarized current via three complementary techniques: tunneling magnetoresistance, tunneling spin polarization, and x-ray magnetic circular dichroism. Trilayer device structures with independently addressable magnetic layers will also be explored.Intellectual Merit: This project may spearhead a paradigm shift for all-electrical spintronics. Present efforts focus on injecting spins from ferromagnets into non-magnetic materials. However, spin-injection has crippled progress, particularly for semiconductor-based devices. The proposed devices induce a spin-polarization in a non-magnetic conduction channel by reflection off an insulating magnetic gate, thereby obviating the difficulties of injection. This project will develop the building blocks for a series of more complex device architectures able to deliver electrically tunable spin-polarized currents.Broader Impacts: This transformational research may ease the integration of spintronics with existing back-end semiconductor processing, thereby substantially reducing barriers to commercial spintronics. This program integrates teaching and multidisciplinary training of undergraduate and graduate students, including those from under-represented groups, by unifying physics, engineering, and materials concepts, and by developing hands-on spintronics experiments for high school and undergraduate laboratories. This work enhances infrastructure via a new collaboration between the University of South Florida and the Advanced Light Source.