Doping-induced magnetic phase transition enables all-electrical spin control in CrSBr

Van der Waals antiferromagnetic semiconductors are promising platforms for energy-efficient two-dimensional spintronics. However, their intrinsic spin degeneracy and the difficulty of achieving electrical spin control pose major challenges for practical device implementation. Here, we present a distinct spintronic platform based on an antiferromagnetic semiconductor CrSBr, in which carrier doping induced by gate-controlled intercalation drives a reversible, zero-field antiferromagnetic to ferromagnetic phase transition, enabling direct and full electrical control of both magnetic order and spin polarization. Exploiting this transition, we engineer CrSBr/graphene heterostructures that leverage interfacial charge transfer to spatially pattern magnetic phases, resulting in lateral spin valves with gate-controlled spin polarization reversal, all without ferromagnetic contacts. Crucially, this mechanism also enables electrical switching of magnetic order via spin-transfer torque at ultralow current densities (<103 A/cm2), demonstrating its efficiency and device compatibility. These findings open a new paradigm for reconfigurable, all-electrical spintronic systems based on van der Waals antiferromagnetic semiconductors. Electrical doping and charge transfer in 2D antiferromagnet CrSBr reversibly switch its magnetic state, enabling gate-tunable spin valves and ultralow-power spin control without ferromagnetic contacts, advancing fully electrical 2D spintronics.