Strong Orientation-Dependent Spin-Orbit Torque in Thin Films of the Antiferromagnet Mn2Au

Antiferromagnets with zero net magnetic moment, strong anti-interference, and ultrafast switching speed are potentially competitive in high-density information storage. The body-centered tetragonal antiferromagnet Mn2Au with opposite-spin sublattices is a unique metallic material for Neel-order spin-orbit-torque (SOT) switching. We investigate the SOT switching in quasiepitaxial (103), (101) and (204) Mn2Au films prepared by a simple magnetron sputtering method. We demonstrate current-induced antiferromagnetic moment switching in all of the prepared Mn2Au films by using a short current pulse at room temperature, whereas differently oriented films exhibit distinguished switching characters. A direction-independent reversible switching is attained in Mn2Au (103) films due to negligible magnetocrystalline anisotropy energy, while for Mn2Au (101) and (204) films, the switching is invertible with the current applied along the in-plane easy axis and its vertical axis, but it becomes attenuated seriously during initial switching circles when the current is applied along the hard axis because of the existence of magnetocrystalline anisotropy energy. Besides the fundamental significance, the strong orientation-dependent SOT switching, which is not realized, irrespective of ferromagnet and antiferromagnet, provides versatility for spintronics.