Peter Grünberg Institut (PGI-9) and JARA-Fundamentals of Future Information Technology, Forschungszentrum Jülich, 52425 Jülich, Germany.
Nano Lett. 2012 Sep 12;12(9):4437-43. doi: 10.1021/nl301052g. Epub 2012 Aug 21.
We report on the conditions necessary for the electrical injection of spin-polarized electrons into indium nitride nanowires synthesized from the bottom up by molecular beam epitaxy. The presented results mark the first unequivocal evidence of spin injection into III-V semiconductor nanowires. Utilizing a newly developed preparation scheme, we are able to surmount shadowing effects during the metal deposition. Thus, we avoid strong local anisotropies that arise if the ferromagnetic leads are wrapping around the nanowire. Using a combination of various complementary techniques, inter alia the local Hall effect, we carried out a comprehensive investigation of the coercive fields and switching behaviors of the cobalt micromagnetic spin probes. This enables the identification of a range of aspect ratios in which the mechanism of magnetization reversal is single domain switching. Lateral nanowire spin valves were prepared. The spin relaxation length is demonstrated to be about 200 nm, which provides an incentive to pursue the route toward nanowire spin logic devices.
我们报告了通过分子束外延自下而上合成的氮化铟纳米线中进行自旋极化电子电注入所需的条件。所呈现的结果标志着首次明确证明了向 III-V 半导体纳米线中注入自旋。利用新开发的制备方案，我们能够克服金属沉积过程中的阴影效应。因此，如果铁磁引线缠绕在纳米线上，我们可以避免出现强烈的各向异性。我们使用各种互补技术的组合，包括局部霍尔效应，对钴微磁自旋探针的矫顽场和切换行为进行了全面研究。这使得能够确定一系列纵横比，其中磁化反转的机制是单畴切换。制备了横向纳米线自旋阀。证明自旋弛豫长度约为 200nm，这为追求纳米线自旋逻辑器件的路线提供了动力。
