Illustration of the origin of the spin-orbit torque in a simple Rashba model. Left figure shows distribution of spin at the Fermi level when no electric field is applied. Right figure shows redistributions of electrons due to applied electric field, which results in a current flowing along the electric field, as well as in a net spin-polariation.
Relativistic Neel-Order Fields Induced by Electrical Current in Antiferromagnets
Abstract
We predict that a lateral electrical current in antiferromagnets can induce nonequilibrium Néel-order fields, i.e., fields whose sign alternates between the spin sublattices, which can trigger ultrafast spin-axis reorientation. Based on microscopic transport theory calculations we identify staggered current-induced fields analogous to the intraband and to the intrinsic interband spin-orbit fields previously reported in ferromagnets with a broken inversion-symmetry crystal. To illustrate their rich physics and utility, we consider bulk Mn 2 Au with the two spin sublattices forming inversion partners, and a 2D square-lattice antiferromagnet with broken structural inversion symmetry modeled by a Rashba spin-orbit coupling. We propose an antiferromagnetic memory device with electrical writing and reading.