Electrical evaluation of the alternating spin current generated via spin-vorticity coupling
Electrical evaluation of the alternating spin current generated via spin-vorticity coupling
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DOI：
10.1103/physrevb.102.104406
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发表时间：
2020-09
影响因子：
3.7
通讯作者：
S. Tateno;Genki Okano;M. Matsuo;Y. Nozaki
中科院分区：
文献类型：
--
作者：
S. Tateno;Genki Okano;M. Matsuo;Y. Nozaki
在许多相互作用的电子系统中，电子的微观自旋角动量与电流中的宏观角动量一起沿着，即，涡度这种自旋-涡旋耦合扩展了自旋电子器件材料的选择。在本文中，我们评估的自旋涡度耦合产生的交变自旋电流的大小与千兆赫兹阶表面声波在铜薄膜。我们用基于逆自旋霍尔效应的电学方法测量了吉赫交变自旋电流。从自旋电流的幅度，我们可以确定的转换效率的角动量之间的本地晶格旋转和电子自旋的铜膜。该转换效率比液汞湍流中通过千赫兹级涡产生自旋电流的情况高四个数量级[M。Matsuo，Phys. Rev. B 96，020401（R）（2017）2469-995010.1103/PhysRevB.96.020401]。这种巨大的转换效率归因于晶格旋转和电子自旋之间的能量尺度比液体涡旋的情况下更小的不一致性。
In many interacting-electron systems, the microscopic spin angular momentum of electrons is conserved along with the macroscopic angular momentum in electrical current flows, i.e., vorticity. Such spin-vorticity coupling expands the choice of materials for spintronics devices. In this paper, we evaluate the magnitude of an alternating spin current generated by the spin-vorticity coupling with a gigahertz-order surface acoustic wave in a Cu thin film. We measure the gigahertz alternating spin current by an electrical method based on the inverse spin-Hall effect. From the amplitude of the spin current, we can determine the conversion efficiency of the angular momentum between local lattice rotation and electron spin in the Cu film. The conversion efficiency is four orders of magnitude larger than the case of spin current generation via kilohertz-order vorticity in turbulent flow of liquid mercury [M. Matsuo , Phys. Rev. B 96, 020401(R) (2017)2469-995010.1103/PhysRevB.96.020401]. Such a huge conversion efficiency is attributable to a smaller inconsistency of energy scale between lattice rotation and electron spin than the case of liquid vorticity.