Surface Coverage Dependence of Spin-to-Charge Current across Pt/MoS2/Y3Fe5O12 Layers via Longitudinal Spin Seebeck Effect.
Surface Coverage Dependence of Spin-to-Charge Current across Pt/MoS2/Y3Fe5O12 Layers via Longitudinal Spin Seebeck Effect.
复制标题
DOI：
10.1021/acs.jpclett.0c01502
复制
发表时间：
2020-06
期刊：
影响因子：
--
通讯作者：
Won‐Yong Lee;No‐Won Park;Min‐Sung Kang;Gil-Sung Kim;Ho Won Jang;E. Saitoh;Sang‐Kwon Lee
中科院分区：
文献类型：
--
作者：
Won‐Yong Lee;No‐Won Park;Min‐Sung Kang;Gil-Sung Kim;Ho Won Jang;E. Saitoh;Sang‐Kwon Lee
在纵向自旋塞贝克效应（LSSE）测量中，反自旋霍尔效应（ISHE）产生的电压受正常金属（NM）的自旋霍尔角、铁磁材料（FM）的质量和磁性能以及NM和FM双层之间的界面条件等因素的影响。具体来说，通过LSSE器件的纳米/调频系统的界面条件对决定自旋电流注入纳米层的效率起着至关重要的作用。在这封信中，我们报告了一种通过中间层的表面覆盖来控制Pt/Y3Fe5O12 （YIG）界面上Pt层注入自旋电流效率的新方法。采用化学气相沉积法在铂层和YIG层之间插入了一层连续的、大面积的多层二硫化钼（MoS2）薄膜。我们发现，当大面积多层MoS2薄膜存在时，与Pt/YIG双分子层相比，Pt/MoS2/YIG三层中测量的ishe感应电压和理论计算的自旋电流分别增加了约510%和470%。感应电压和自旋电流对表面电导非常敏感，在LSSE测量中，表面电导受多层MoS2薄膜表面覆盖的影响。此外，理论计算的自旋电流和自旋混合电导在三层几何结构中与实验观测结果在质量上吻合较好。这些测量结果使我们能够解释界面条件对自旋输运中自旋塞贝克效应的影响。
The voltage induced by the inverse spin Hall effect (ISHE) is affected by several factors, including the spin Hall angle of the normal metal (NM), the quality and magnetic properties of the ferromagnetic material (FM), and the interface conditions between the NM and FM bilayers in longitudinal spin Seebeck effect (LSSE) measurement. Specifically, the interface conditions in NM/FM systems via LSSE devices play a crucial role in determining the efficiency of spin current injection into the NM layer. In this letter, we report a new approach to controlling the efficiency of spin current injection into a Pt layer across a Pt/Y3Fe5O12 (YIG) interface by surface coverage of the intermediate layer. A continuous, large-area multilayer molybdenum dichalcogenide (MoS2) thin film grown by chemical vapor deposition is inserted between the Pt and YIG layers in the LSSE configuration. We found that when the large-area multilayer MoS2 film was present, the measured ISHE-induced voltage and theoretically calculated spin current in the Pt/MoS2/YIG trilayer increased by approximately 510% and 470%, respectively, compared to those of a Pt/YIG bilayer. The induced voltage and spin current were very sensitive to the surface conductance, which was affected by the surface coverage of the multilayer MoS2 films in the LSSE measurement. Furthermore, the theoretically calculated spin current and spin mixing conductance in the trilayer geometry are in qualitatively good agreement with the experimental observations. These measurements enable us to explain the effect of the interface conditions on the spin Seebeck effect in spin transport.