Valley degree of freedom, an intrinsic property of electrons, provides a novel dimension for information storage and processing. For most conventional valleytronic materials, however, stable and tunable valley polarization (VP) is usually realized based on spin−orbit coupling (SOC), which significantly limits material choices and operational flexibility. Altermagnetism — a novel magnetic order characterized by compensated magnetic order with vanishing net magnetization, broken inversion symmetry, and momentum-dependent spin splitting — offers a revolutionary solution to overcome this bottleneck. Originating from the coupling of altermagnetism and ferrovalley (FV) physics, the altermagnetic ferrovalley (AMFV) materials enable robust, tunable, and spontaneous spin-valley locking independently of strong SOC. This review systematically outlines the advances in AMFV materials. It begins by revisiting the types and limitations of traditional FV systems, then delves into the physical nature of altermagnetism and the symmetry principles underlying its integration with valley physics. Subsequently, it categorizes and reviews the latest theoretical and experimental progress on representative AMFV materials (e.g., V2Se2O, Fe2MX4), focusing on elucidating their multi-degree-of-freedom coupling characteristics (such as spin-valley-optical coupling) and their modulation mechanisms under external stimuli, including strain, electric field, sliding, twisting, and proximity effects. These AMFV systems hold enormous application potential in valley tunnel junctions and non-volatile memory, yet they still face challenges such as material scarcity, unclear mechanisms, and a lack of device-level exploration. Future efforts should leverage the synergy of high-throughput computation, advanced characterization techniques, and device development to drive breakthroughs and accelerate the development of next-generation information technologies.
Li et al. (Thu,) studied this question.