Antiferromagnets for spintronics

Upon their original discovery, antiferromagnets were considered interesting magnetic materials, but without much practical relevance. This sentiment changed upon the development of spintronics, where the electrons’ spin degree of freedom is utilized for new functionality in electronic devices. In this context antiferromagnets first found application as passive elements, where their insensitivity to applied magnetic fields allowed them to provide reference magnetic orientations via the exchange-bias effect. More recently it has been recognized that antiferromagnets can play a more active role in spintronics; namely they can generate, support, and manipulate spin currents. In fact, the magnetic structure of antiferromagnets may play a profound role in spin-transport phenomena, giving rise to new transport phenomena. We will briefly review both the passive and active roles that antiferromagnets may play for spintronics and provide a perspective for future opportunities.