We have studied spin-orbit torque (SOT) magnetization switching in a (Ga,Mn)(As,P) film with vertically-graded magnetic anisotropy. The magnetization switching chirality during current scans reveals that strain-induced Dresselhaus-type spin-orbit field does the major role for spin polarization of carriers causing SOT in the system. The volume fraction of SOT magnetization switching significantly depends on the magnitude and direction of the applied bias field. This feature leads to the realization of stable multilevel magnetic states in composition-graded (Ga,Mn)(As,P) film. The experiment demonstrates that multiple magnetic state can be robustly set by using appropriate bias fields. This characteristic can be used to realize SOT-driven multi-state memories and/or memristor devices, which are key ingredients for neuromorphic computing.
Bibliographical noteFunding Information:
This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) of Korea (2021R1A2C1003338); by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (2022M3F3A2A03014536); by the NRF under the BK21 FOUR program at Korea University, Initiative for Science Frontiers on Upcoming Challenges; by Korea University Grant; and by National Science Foundation Grant DMR 1905277. Part of this study was performed using facilities at IBS Center for Correlated Electron Systems, Seoul National University.
© 2023 Author(s).
ASJC Scopus subject areas
- Physics and Astronomy(all)