Theory of Rashba Torques

Abstract

This chapter focuses on the theory of current-driven Rashba torque, a special type of spin–orbit mediated spin torque that requires broken spatial-inversion symmetry. This specific form of spin-orbit interaction enables the electrical generation of a non-equilibrium spin density that yields both damping-like and field-like torques on the local magnetic moments. We review the recent results obtained in (ferromagnetic and antiferromagnetic) two-dimensional electron gases, bulk magnetic semiconductors, and at the surface of topological insulators. We conclude by summarizing recent experimental results that support the emergence of Rashba torques in magnets lacking inversion symmetry.