Enhancement of spin-orbit torque efficiency by tailoring interfacial spin-orbit coupling in Pt-based magnetic multilayers  

作　　者：Wenqiang Wang Gengkuan Zhu Kaiyuan Zhou Xiang Zhan Zui Tao Qingwei Fu Like Liang Zishuang Li Lina Chen Chunjie Yan Haotian Li Tiejun Zhou Ronghua Liu 王文强;朱耿宽;周恺元;战翔;陶醉;付清为;梁力克;李子爽;陈丽娜;晏春杰;李浩天;周铁军;刘荣华(National Laboratory of Solid State Microstructures,School of Physics and Collaborative Innovation Center of Advanced Microstructures,Nanjing University,Nanjing 210093,China;New Energy Technology Engineering Laboratory of Jiangsu Provence and School of Science,Nanjing University of Posts and Telecommunications,Nanjing 210023,China;Centre for Integrated Spintronic Devices,School of Electronics and Information,Hangzhou Dianzi University,Hangzhou 310018,China)

机构地区：[1]National Laboratory of Solid State Microstructures,School of Physics and Collaborative Innovation Center of Advanced Microstructures,Nanjing University,Nanjing 210093,China [2]New Energy Technology Engineering Laboratory of Jiangsu Provence and School of Science,Nanjing University of Posts and Telecommunications,Nanjing 210023,China [3]Centre for Integrated Spintronic Devices,School of Electronics and Information,Hangzhou Dianzi University,Hangzhou 310018,China

出　　处：《Chinese Physics B》2022年第9期146-151,共6页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.11774150,12074178,11874135,and 12004171);the Applied Basic Research Programs of the Science and Technology Commission Foundation of Jiangsu Province,China(Grant No.BK20200309);the Open Research Fund of Jiangsu Provincial Key Laboratory for Nanotechnology,Key Research and Development Program of Zhejiang Province,China(Grant No.2021C01039);the Scientific Foundation of Nanjing University of Posts and Telecommunications(Grant No.NY220164).

摘　　要：We study inserting Co layer thickness-dependent spin transport and spin-orbit torques(SOTs)in the Pt/Co/Py trilayers by spin-torque ferromagnetic resonance.The interfacial perpendicular magnetic anisotropy(IPMA)energy density(Ks=2.7 erg/cm^(2),1 erg=10^(-7) J),which is dominated by interfacial spin-orbit coupling(ISOC)in the Pt/Co interface,total effective spin-mixing conductance(G↑↓eff,tot=0.42×10^(15) Ω^(-1)·m^(-2))and two-magnon scattering(βTMS=0.46 nm2)are first characterized,and the damping-like torque(ξDL=0.103)and field-like torque(ξFL=-0.017)efficiencies are also calculated quantitatively by varying the thickness of the inserting Co layer.The significant enhancement of ξDL and ξFL in Pt/Co/Py than Pt/Py bilayer system originates from the interfacial Rashba-Edelstein effect due to the strong ISOC between Co-3d and Pt-5d orbitals at the Pt/Co interface.Additionally,we find a considerable out-of-plane spin polarization SOT,which is ascribed to the spin anomalous Hall effect and possible spin precession effect due to IPMA-induced perpendicular magnetization at the Pt/Co interface.Our results demonstrate that the ISOC of the Pt/Co interface plays a vital role in spin transport and SOTs-generation.Our finds offer an alternative approach to improve the conventional SOTs efficiencies and generate unconventional SOTs with out-of-plane spin polarization to develop low power Pt-based spintronic via tailoring the Pt/FM interface.

关 键 词：spin-orbit torque interfacial Rashba-Edelstein effect spin-torque efficiency spin-torque ferromagnetic resonance 

分 类 号：O469[理学—凝聚态物理]