Spin-orbit torque manipulation of sub-terahertz magnons in antiferromagnetic α-Fe2O3

Dongsheng Yang; Taeheon Kim; Kyusup Lee; Chang Xu; Yakun Liu; Fei Wang; Shishun Zhao; Dushyant Kumar; Hyunsoo Yang

doi:10.1038/s41467-024-48431-w

Spin-orbit torque manipulation of sub-terahertz magnons in antiferromagnetic α-Fe₂O₃

Nat Commun. 2024 May 14;15(1):4046. doi: 10.1038/s41467-024-48431-w.

Authors

Dongsheng Yang^#¹, Taeheon Kim^#^{1

2}, Kyusup Lee¹, Chang Xu¹, Yakun Liu¹, Fei Wang¹, Shishun Zhao¹, Dushyant Kumar¹, Hyunsoo Yang³

Affiliations

¹ Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore.
² Electro-Medical Device Research Centre, Korea Electrotechnology Research Institute, Ansan, Republic of Korea.
³ Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore. eleyang@nus.edu.sg.

^# Contributed equally.

Abstract

The ability to electrically manipulate antiferromagnetic magnons, essential for extending the operating speed of spintronic devices into the terahertz regime, remains a major challenge. This is because antiferromagnetic magnetism is challenging to perturb using traditional methods such as magnetic fields. Recent developments in spin-orbit torques have opened a possibility of accessing antiferromagnetic magnetic order parameters and controlling terahertz magnons, which has not been experimentally realised yet. Here, we demonstrate the electrical manipulation of sub-terahertz magnons in the α-Fe₂O₃/Pt antiferromagnetic heterostructure. By applying the spin-orbit torques in the heterostructure, we can modify the magnon dispersion and decrease the magnon frequency in α-Fe₂O₃, as detected by time-resolved magneto-optical techniques. We have found that optimal tuning occurs when the Néel vector is perpendicular to the injected spin polarisation. Our results represent a significant step towards the development of electrically tunable terahertz spintronic devices.