Su Shu Hsuan, Chong Cheong-Wei, Lee Jung-Chuan, Chen Yi-Chun, Marchenkov Vyacheslav Viktorovich, Huang Jung-Chun Andrew
Department of Physics, National Cheng Kung University, Tainan 701401, Taiwan.
Sheng Chuang Technology Company, Taichung 407330, Taiwan.
Nanomaterials (Basel). 2022 Oct 20;12(20):3687. doi: 10.3390/nano12203687.
The spin-to-charge conversion in Permalloy (Py)/Cu/BiSe is tunable by changing the Cu layer thickness. The conversion rate was studied using the spin pumping technique. The inverse Edelstein effect (IEE) length λ is found to increase up to ~2.7 nm when a 7 nm Cu layer is introduced. Interestingly, the maximized λ is obtained when the effective spin-mixing conductance (and thus J) is decreased due to Cu insertion. The monotonic increase in λ with decreasing J suggests that the IEE relaxation time (τ) is enhanced due to the additional tunnelling barrier (Cu layer) that limits the interfacial transmission rate. The results demonstrate the importance of interface engineering in the magnetic heterostructure of Py/topological insulators (TIs), the key factor in optimizing spin-to-charge conversion efficiency.
通过改变铜层厚度,坡莫合金(Py)/铜/铋硒中的自旋到电荷转换是可调的。使用自旋泵浦技术研究了转换率。当引入7纳米厚的铜层时,发现逆埃德尔斯坦效应(IEE)长度λ增加到约2.7纳米。有趣的是,当由于插入铜而导致有效自旋混合电导(进而J)降低时,可获得最大化的λ。随着J的减小,λ单调增加,这表明由于限制界面传输速率的额外隧穿势垒(铜层),IEE弛豫时间(τ)得到了增强。结果证明了界面工程在Py/拓扑绝缘体(TIs)磁性异质结构中的重要性,这是优化自旋到电荷转换效率的关键因素。