Sign Change of Spin-Orbit Torque in Pt/NiO/CoFeB Structures

Dapeng Zhu; Tianrui Zhang; Xiao Fu; Runrun Hao; Amir Hamzić; Huaiwen Yang; Xueying Zhang; Hui Zhang; Ao Du; Danrong Xiong; Kewen Shi; Shishen Yan; Shufeng Zhang; Albert Fert; Weisheng Zhao

doi:10.1103/PhysRevLett.128.217702

Sign Change of Spin-Orbit Torque in Pt/NiO/CoFeB Structures

Phys Rev Lett. 2022 May 27;128(21):217702. doi: 10.1103/PhysRevLett.128.217702.

Authors

Dapeng Zhu^{1

2}, Tianrui Zhang¹, Xiao Fu^{1

2}, Runrun Hao^{1

2}, Amir Hamzić^{1

3}, Huaiwen Yang^{1

2}, Xueying Zhang^{1

2}, Hui Zhang¹, Ao Du¹, Danrong Xiong¹, Kewen Shi¹, Shishen Yan⁴, Shufeng Zhang⁵, Albert Fert^{1

6}, Weisheng Zhao^{1

2}

Affiliations

¹ Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China.
² Beihang-Goertek Joint Microelectronics Institute, Qingdao Research Institute, Beihang University, Qingdao 266000, China.
³ Department of Physics, Faculty of Science, University of Zagreb, Zagreb HR-10001, Croatia.
⁴ School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China.
⁵ Department of Physics, University of Arizona, Tucson, Arizona 85721, USA.
⁶ Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, Palaiseau 91767, France.

PMID: 35687442
DOI: 10.1103/PhysRevLett.128.217702

Abstract

Antiferromagnetic insulators have recently been proved to support spin current efficiently. Here, we report the dampinglike spin-orbit torque (SOT) in Pt/NiO/CoFeB has a strong temperature dependence and reverses the sign below certain temperatures, which is different from the slight variation with temperature in the Pt/CoFeB bilayer. The negative dampinglike SOT at low temperatures is proposed to be mediated by the magnetic interactions that tie with the "exchange bias" in Pt/NiO/CoFeB, in contrast to the thermal-magnon-mediated scenario at high temperatures. Our results highlight the promise to control the SOT through tuning the magnetic structure in multilayers.