Altermagnetic spintronics

The research landscape of magnetism has been recently enriched by the discovery of altermagnetism. It is an unconventional phase of matter characterized by a d-wave (or higher even-parity-wave) collinear compensated spin ordering, which enables strongly spin-polarized currents in the absence of magnetization, and features fast spin dynamics. Simultaneously, on the applied magnetism front, spintronic memories based on conventional ferromagnets are currently turning from a niche to a mass produced integrated-circuit technology as they start to complement semiconductors on advanced-node microprocessor chips. Our review connects these two rapidly developing science and technology fields by discussing how the unique signatures of altermagnetism can impact the functionality and scalability of future spintronic devices. As a reference, we first briefly recall the merits and physical limitations of the present ferromagnetic spintronic technology, and of proof-of-concept spintronic devices based on conventional collinear antiferromagnets and non-collinear compensated magnets. The main part of the review then focuses on physical concepts of the altermagnetic spintronics, and its potential interplay with ferroelectricity or superconductivity. We conclude with an outlook on the nascent experimental research of altermagnetic spintronics, and on the role of relativistic phenomena.