Rashba–Edelstein effect in altermagnetic twisted bilayers

Altermagnetic materials are a new type of magnetic materials that have recently garnered significant attention due to their exceptional properties, while the Rashba-Edelstein effect (REE) serves as a crucial charge-to-spin conversion mechanism. In this study, we explore the commonalities in symmetry dependence between altermagnetic materials and the occurrence of the REE. Utilizing a self-developed program for quantifying the REE, we calculate the REE intensity of altermagnetic materials after breaking symmetry constraints via twisting. By comparing the REE intensities between altermagnetic materials with weak spin-orbit coupling (SOC) and transition metal dichalcogenides with strong-SOC following symmetry breaking through twisting, it is found that efficient REE can be achieved in weak-SOC altermagnetic materials through symmetry regulation. This result breaks the traditional reliance of the REE on strong-SOC materials, providing theoretical support for the material design and functional optimization of next generation spintronic devices.