Giant Enhancements of Perpendicular Magnetic Anisotropy and Spin-Orbit Torque by a MoS2 Layer

Qidong Xie; Weinan Lin; Baishun Yang; Xinyu Shu; Shaohai Chen; Liang Liu; Xiaojiang Yu; Mark B H Breese; Tiejun Zhou; Ming Yang; Zheng Zhang; Shijie Wang; Hongxin Yang; Jianwei Chai; Xiufeng Han; Jingsheng Chen

doi:10.1002/adma.201900776

Giant Enhancements of Perpendicular Magnetic Anisotropy and Spin-Orbit Torque by a MoS₂ Layer

Adv Mater. 2019 May;31(21):e1900776. doi: 10.1002/adma.201900776. Epub 2019 Apr 8.

Authors

Qidong Xie^{1

2}, Weinan Lin¹, Baishun Yang^{3

4}, Xinyu Shu¹, Shaohai Chen¹, Liang Liu¹, Xiaojiang Yu⁵, Mark B H Breese⁵, Tiejun Zhou⁶, Ming Yang², Zheng Zhang², Shijie Wang², Hongxin Yang⁴, Jianwei Chai², Xiufeng Han³, Jingsheng Chen^{1

7}

Affiliations

¹ Department of Materials Science and Engineering, National University of Singapore, Singapore, 117575, Singapore.
² Department of Electronic Material, Institute of Material Research and Engineering, A*STAR, Singapore, 138634, Singapore.
³ Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100190, China.
⁴ CAS Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China.
⁵ Singapore Synchrotron Light Source, National University of Singapore, Singapore, 117575, Singapore.
⁶ College of electronics and information, Hangzhou Dianzi University, Hangzhou, 310018, China.
⁷ Suzhou Research Institute, National University of Singapore, Suzhou, 215123, China.

PMID: 30957913
DOI: 10.1002/adma.201900776

Abstract

2D transition metal dichalcogenides have attracted much attention in the field of spintronics due to their rich spin-dependent properties. The promise of highly compact and low-energy-consumption spin-orbit torque (SOT) devices motivates the search for structures and materials that can satisfy the requirements of giant perpendicular magnetic anisotropy (PMA) and large SOT simultaneously in SOT-based magnetic memory. Here, it is demonstrated that PMA and SOT in a heavy metal/transition metal ferromagnet structure, Pt/[Co/Ni]₂ , can be greatly enhanced by introducing a molybdenum disulfide (MoS₂ ) underlayer. According to first-principles calculation and X-ray absorption spectroscopy (XAS), the enhancement of the PMA is ascribed to the modification of the orbital hybridization at the interface of Pt/Co due to MoS₂ . The enhancement of SOT by the role played by MoS₂ is explained, which is strongly supported by the identical behavior of SOT and PMA as a function of Pt thickness. This work provides new possibilities to integrate 2D materials into promising spintronics devices.

Keywords: 2D materials; orbital hybridization; perpendicular magnetic anisotropy; spin-orbit torque.

Abstract

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