Controlling the Competition between Optically Induced Ultrafast Spin-Flip Scattering and Spin Transport in Magnetic Multilayers
Controlling the Competition between Optically Induced Ultrafast Spin-Flip Scattering and Spin Transport in Magnetic Multilayers
复制标题
DOI：
10.1103/physrevlett.110.197201
复制
发表时间：
2013-05-07
影响因子：
8.6
通讯作者：
Mathias, Stefan
中科院分区：
文献类型：
--
作者：
Turgut, Emrah;La-o-Vorakiat, Chan;Mathias, Stefan
磁性材料中的超快动力学研究为更深入地了解固态物质中的相关现象提供了丰富的机会，因为所涉及的许多基本微观机制尚不清楚，仍在探索中。最近，两种不同的机制被提出来解释超快激光诱导磁化动力学：自旋电流和自旋翻转散射。在这项工作中，我们使用多层的Fe和Ni与不同的金属和绝缘体作为间隔材料，最终表明，自旋电流可以有显着的贡献，光致磁化动力学，除了自旋翻转散射过程。此外，我们可以控制这两个过程之间的竞争，并在某些情况下完全抑制层间自旋电流作为样品经历快速退磁。最后，通过颠倒Fe/Ni层的顺序，我们实验表明，自旋电流在我们的样本中是定向的，主要从顶层流向底层。
The study of ultrafast dynamics in magnetic materials provides rich opportunities for greater fundamental understanding of correlated phenomena in solid-state matter, because many of the basic microscopic mechanisms involved are as-yet unclear and are still being uncovered. Recently, two different possible mechanisms have been proposed to explain ultrafast laser induced magnetization dynamics: spin currents and spin-flip scattering. In this work, we use multilayers of Fe and Ni with different metals and insulators as the spacer material to conclusively show that spin currents can have a significant contribution to optically induced magnetization dynamics, in addition to spin-flip scattering processes. Moreover, we can control the competition between these two processes, and in some cases completely suppress interlayer spin currents as a sample undergoes rapid demagnetization. Finally, by reversing the order of the Fe/Ni layers, we experimentally show that spin currents are directional in our samples, predominantly flowing from the top to the bottom layer.