Perspectives on spin hydrodynamics in ferromagnetic materials

Highlights: • Review of theoretical results on spin hydrodynamics. • Physical interpretation of hydrodynamic equations. • Review of predicted long-range transport solutions in ferromagnetic nanowires. • Perspectives on future directions and challenges. -- Abstract: The field of spin hydrodynamics aims to describe magnetization dynamics from a fluid perspective. For ferromagnetic materials, there is an exact mapping between the Landau-Lifshitz equation and a set of dispersive hydrodynamic equations. This analogy provides ample opportunities to explore novel magnetization dynamics and magnetization states that can lead to potential applications that rely entirely on magnetic materials, for example, long-distance transport of information. This article provides an overview of the theoretical foundations of spin hydrodynamics and their physical interpretation in the context of spin transport. We discuss other proposed applications for spin hydrodynamics as well as our view on challenges and future research directions.