Tailoring magnetic anisotropy by graphene-induced selective skyhook effect on 4f-metals.
Tailoring magnetic anisotropy by graphene-induced selective skyhook effect on 4f-metals.
复制标题
通过石墨烯诱导的 4f 金属选择性天钩效应调整磁各向异性
作者：
A. Herman;S. Kraus;S. Tsukamoto;L. Spieker;V. Caciuc;T. Lojewski;D. Günzing;J. Dreiser;B. Delley;K. Ollefs;T. Michely;N. Atodiresei;H. Wende
从宏观重型永磁体到纳米器件，稀土金属磁性的精确控制对于我们日常生活中的许多应用至关重要。因此，详细了解和操纵 4f 金属的磁性是进一步提高未来应用的功能化和效率的关键。我们提出了一种由镝-铱表面合金组成的概念验证方法，其中石墨烯吸附使我们能够定制其磁性。通过将石墨烯吸附到长程有序二维镝-铱表面合金上，磁性 4f 金属原子被选择性地从表面合金中升起。由于操纵表面合金内的几何结构，这种选择性天钩效应在镝原子中引入了巨大的磁各向异性。通过我们结合理论和实验的方法来引入和证明这个概念，可以轻松、明确地理解其基本机制。我们的研究为如何改变 4f 原子周围的晶体场及其磁各向异性的替代途径奠定了基础。
From macroscopic heavy-duty permanent magnets to nanodevices, the precise control of the magnetic properties in rare-earth metals is crucial for many applications used in our daily life. Therefore, a detailed understanding and manipulation of the 4f-metals’ magnetic properties are key to further boosting the functionalization and efficiency of future applications. We present a proof-of-concept approach consisting of a dysprosium-iridium surface alloy in which graphene adsorption allows us to tailor its magnetic properties. By adsorbing graphene onto a long-range ordered two-dimensional dysprosium-iridium surface alloy, the magnetic 4f-metal atoms are selectively lifted from the surface alloy. This selective skyhook effect introduces a giant magnetic anisotropy in dysprosium atoms as a result of manipulating its geometrical structure within the surface alloy. Introducing and proving this concept by our combined theoretical and experimental approach provides an easy and unambiguous understanding of its underlying mechanism. Our study sets the ground for an alternative path on how to modify the crystal field around 4f-atoms and therefore their magnetic anisotropies.