Title: Spin current leakage and Onsager reciprocity in interfacial spin-charge interconversion Show Chinese title

Title: 界面自旋-电荷转换中的自旋电流泄漏和昂萨格对称性

Abstract: Experimental investigations of spin-charge interconversion in magnetic bilayers comprising a ferromagnet adjacent to a topological insulator have reported scattered results on the spin-charge and charge-spin conversion efficiency. Attempting to reconcile these contradicting experimental results, we develop a phenomenological theory of spin-charge interconversion accounting for both interfacial interconversion through the spin galvanic effect, also called the Rashba-Edelstein effect, as well as bulk interconversion via the spin Hall effect. We find that the spin current leakage into the nonmagnetic metal plays a central role during the spin-to-charge and charge-to-spin conversion, leading to dissymmetric interconversion processes. In particular, spin-to-charge conversion is much less sensitive to the spin current absorption in the nonmagnetic metal than charge-to-spin conversion. This suggests that spin pumping is a more trustable technique to extract the interfacial Rashba parameter than spin-orbit torque. Show Chinese abstract

Abstract: 对由铁磁体和拓扑绝缘体组成的磁性双层结构中的自旋-电荷相互转换进行的实验研究，关于自旋-电荷和电荷-自旋转换效率的报告结果存在分歧。 试图调和这些矛盾的实验结果，我们建立了一个经验性的自旋-电荷相互转换理论，该理论考虑了通过自旋伽利略效应（也称为Rashba-Edelstein效应）的界面相互转换，以及通过自旋霍尔效应的体相互转换。 我们发现，在自旋到电荷和电荷到自旋转换过程中，自旋电流泄漏到非磁性金属中起着核心作用，导致不对称的相互转换过程。 特别是，自旋到电荷的转换比电荷到自旋的转换对非磁性金属中的自旋电流吸收不那么敏感。 这表明，自旋泵浦是一种比自旋轨道扭矩更可靠的方法来提取界面Rashba参数。