2D van der Waals magnets: from fundamental physics to applications

Abstract: Magnetism has played a central role in the long and rich history of modern condensed matter physics, with many foundational insights originating from theoretical studies of two-dimensional (2D) spin systems. The discovery of 2D van der Waals (vdW) magnets has revolutionized this area by providing real, atomically thin magnetic systems for experimental investigation. Since the first experimental reports of antiferromagnetic vdW insulators in 2016 - followed by studies on ferromagnetic vdW systems in 2017 - the field has witnessed rapid and expansive growth, with more than two dozen vdW magnetic materials now identified, including both ferro- and antiferromagnets. In this review, we present a comprehensive overview of the major scientific and technological developments in this rapidly evolving field. These include experimental realizations of various 2D spin Hamiltonians as well as unexpected phenomena such as magnetic excitons, Floquet-engineered states, and light-induced metastable magnetic phases. In parallel, 2D vdW magnets have shown significant promise in spintronics and related applications, offering a new platform for engineering quantum functionalities. We organize this review by tracing the historical development of the field, synthesizing key milestones, and highlighting its broader impact across condensed matter physics and materials science. We conclude with an Outlook section that outlines several promising directions for future research, aiming to chart a path forward in this vibrant and still rapidly growing area.