Department of Physics, National Taiwan University, Taipei, 10617, Taiwan.
Center for Condensed Matter Sciences, National Taiwan University, Taipei, 10617, Taiwan.
Sci Rep. 2017 Jul 26;7(1):6612. doi: 10.1038/s41598-017-06861-1.
Ferromagnetic resonance driven spin pumping (FMR-SP) is a novel method to transfer spin current from the ferromagnetic (FM) layer into the adjacent normal metal (NM) layer in an FM/NM bilayer system. Consequently, the spin current could be probed in NM layer via inverse spin Hall effect (ISHE). In spite of numerous ISHE studies on FM/Pt bilayers, LaSrMnO(LSMO)/Pt system has been less explored and its relevant information about interface property (characterized by spin mixing conductance) and spin-charge conversion efficiency (characterized by spin Hall angle) is a matter of importance for the possible applications of spintronic devices. In this work, the technique of FMR-SP has been applied on two series of LSMO/Pt bilayers with the thickness of each layer being varied. The thickness dependences of ISHE voltage allow to extract the values of spin mixing conductance and spin Hall angle of LSMO/Pt bilayers, which are (1.8 ± 0.4) × 10 m and (1.2 ± 0.1) % respectively. In comparison with other FM/Pt systems, LSMO/Pt has comparable spin current density and spin mixing conductance, regardless its distinct electronic structure from other ferromagnetic metals.
铁磁共振驱动的自旋泵浦（FMR-SP）是一种将自旋电流从铁磁（FM）层转移到 FM/NM 双层系统中相邻的正常金属（NM）层的新方法。因此，通过逆自旋霍尔效应（ISHE）可以在 NM 层中探测到自旋电流。尽管在 FM/Pt 双层体系上已经进行了大量的 ISHE 研究，但 LaSrMnO（LSMO）/Pt 体系的研究较少，其界面性质（由自旋混合电导表征）和自旋-电荷转换效率（由自旋霍尔角表征）的相关信息对于自旋电子器件的应用非常重要。在这项工作中，FMR-SP 技术已应用于具有不同层厚的两组 LSMO/Pt 双层体系。ISHE 电压的厚度依赖性允许提取 LSMO/Pt 双层的自旋混合电导和自旋霍尔角的值，分别为（1.8±0.4）×10-11 m 和（1.2±0.1）%。与其他 FM/Pt 体系相比，LSMO/Pt 具有相当的自旋电流密度和自旋混合电导，尽管其电子结构与其他铁磁金属明显不同。
