Current-induced Néel order switching facilitated by magnetic phase transition

Hao Wu; Hantao Zhang; Baomin Wang; Felix Groß; Chao-Yao Yang; Gengfei Li; Chenyang Guo; Haoran He; Kin Wong; Di Wu; Xiufeng Han; Chih-Huang Lai; Joachim Gräfe; Ran Cheng; Kang L Wang

doi:10.1038/s41467-022-29170-2

Current-induced Néel order switching facilitated by magnetic phase transition

Nat Commun. 2022 Mar 28;13(1):1629. doi: 10.1038/s41467-022-29170-2.

Authors

Hao Wu^#^{1

2}, Hantao Zhang^#³, Baomin Wang^{4

5}, Felix Groß⁶, Chao-Yao Yang⁷, Gengfei Li⁸, Chenyang Guo⁹, Haoran He¹⁰, Kin Wong¹⁰, Di Wu¹⁰, Xiufeng Han^{11

9}, Chih-Huang Lai⁷, Joachim Gräfe⁶, Ran Cheng¹², Kang L Wang¹³

Affiliations

¹ Department of Electrical and Computer Engineering, University of California, Los Angeles, CA, 90095, USA. wuhaoiphy@gmail.com.
² Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China. wuhaoiphy@gmail.com.
³ Department of Electrical and Computer Engineering, University of California, Riverside, CA, 92521, USA.
⁴ School of Physical Science and Technology, Ningbo University, Ningbo, 315211, China. wangbaomin@nimte.ac.cn.
⁵ CAS Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China. wangbaomin@nimte.ac.cn.
⁶ Max Planck Institute for Intelligent Systems, Heisenbergstraße 3, Stuttgart, 70569, Germany.
⁷ Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, 30013, Taiwan.
⁸ CAS Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China.
⁹ Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
¹⁰ Department of Electrical and Computer Engineering, University of California, Los Angeles, CA, 90095, USA.
¹¹ Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China.
¹² Department of Electrical and Computer Engineering, University of California, Riverside, CA, 92521, USA. rancheng@ucr.edu.
¹³ Department of Electrical and Computer Engineering, University of California, Los Angeles, CA, 90095, USA. wang@ee.ucla.edu.

^# Contributed equally.

Abstract

Terahertz (THz) spin dynamics and vanishing stray field make antiferromagnetic (AFM) materials the most promising candidate for the next-generation magnetic memory technology with revolutionary storage density and writing speed. However, owing to the extremely large exchange energy barriers, energy-efficient manipulation has been a fundamental challenge in AFM systems. Here, we report an electrical writing of antiferromagnetic orders through a record-low current density on the order of 10⁶ A cm^-2 facilitated by the unique AFM-ferromagnetic (FM) phase transition in FeRh. By introducing a transient FM state via current-induced Joule heating, the spin-orbit torque can switch the AFM order parameter by 90° with a reduced writing current density similar to ordinary FM materials. This mechanism is further verified by measuring the temperature and magnetic bias field dependences, where the X-ray magnetic linear dichroism (XMLD) results confirm the AFM switching besides the electrical transport measurement. Our findings demonstrate the exciting possibility of writing operations in AFM-based devices with a lower current density, opening a new pathway towards pure AFM memory applications.