Spin wave generation by surface acoustic waves
Spin wave generation by surface acoustic waves
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DOI：
10.1063/1.4996102
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发表时间：
2017-07-28
影响因子：
3.2
通讯作者：
Lynch, Christopher S.
中科院分区：
文献类型：
--
作者：
Li, Xu;Labanowski, Dominic;Lynch, Christopher S.
压电基片上的声表面波（SAW）通过磁弹耦合在磁致伸缩薄膜中激发自旋波共振（SWR）。该声学驱动的SWR使得能够激发具有与磁致弹性波矢量匹配的平面内波矢量k的单个自旋波模式。一个二维频域有限元模型，充分耦合弹性动力学，微磁学，压电与界面自旋泵效应考虑在内。它是用来模拟声表面波驱动的驻波比铁磁和压电异质结器件与叉指换能器配置。这些结果，第一次，目前的磁化分量的空间分布，与弹性波，沿沿着传播方向，由于磁阻尼指数衰减。结果还表明，系统的传输速率S21（dB）可以通过外部偏置场和SAW波矢量来调节。磁性薄膜/正常金属界面处的声自旋泵浦导致磁性薄膜中的阻尼增强，从而降低了弹性能量的能量吸收率。磁能和弹性能之间的这种减弱的相互作用导致SAW的较低的倏逝率，这导致较长的距离传播。在强磁弹耦合作用下，声表面波驱动的自旋波可以传播到1200 μ m。结果给出了声自旋泵浦对线宽展宽的贡献的定量指示。出版社：AIP Publishing
Surface acoustic waves ( SAW) on piezoelectric substrates can excite spin wave resonance (SWR) in magnetostrictive films through magnetoelastic coupling. This acoustically driven SWR enables the excitation of a single spin wave mode with an in-plane wave vector k matched to the magnetoelastic wave vector. A 2D frequency domain finite element model is presented that fully couples elastodynamics, micromagnetics, and piezoelectricity with interface spin pumping effects taken into account. It is used to simulate SAW driven SWR on a ferromagnetic and piezoelectric heterostructure device with an interdigital transducer configuration. These results, for the first time, present the spatial distribution of magnetization components that, together with elastic wave, exponentially decays along the propagation direction due to magnetic damping. The results also show that the system transmission rate S21( dB) can be tuned by both an external bias field and the SAW wavevector. Acoustic spin pumping at magnetic film/normal metal interface leads to damping enhancement in magnetic films that decreases the energy absorption rate from elastic energy. This weakened interaction between the magnetic energy and elastic energy leads to a lower evanescence rate of the SAW that results in a longer distance propagation. With strong magnetoelastic coupling, the SAW driven spin wave is able to propagate up to 1200 mu m. The results give a quantitative indication of the acoustic spin pumping contribution to linewidth broadening. Published by AIP Publishing.