Electric field control of Néel spin–orbit torque in an antiferromagnet

Electric field control of spin-orbit torque in ferromagnets¹ has been intensively pursued in spintronics to achieve efficient memory and computing devices with ultralow energy consumption. Compared with ferromagnets, antiferromagnets^2,3 have huge potential in high-density information storage because of their ultrafast spin dynamics and vanishingly small stray field^4-7. However, the manipulation of spin-orbit torque in antiferromagnets using electric fields remains elusive. Here we use ferroelastic strain from piezoelectric materials to switch the uniaxial magnetic anisotropy in antiferromagnetic Mn₂Au films with an electric field of only a few kilovolts per centimetre at room temperature. Owing to the uniaxial magnetic anisotropy, we observe an asymmetric Néel spin-orbit torque^8,9 in the Mn₂Au, which is used to demonstrate an antiferromagnetic ratchet. The asymmetry of the Néel spin-orbit torque and the corresponding antiferromagnetic ratchet can be reversed by the electric field. Our finding sheds light on antiferromagnet-based memories with ultrahigh density and high energy efficiency.