Fully reversible electric-field control of magnetization in Fe3GaTe2/CuInP2S6 heterostructure.

Two-dimensional van der Waals magnetic materials offer a promising platform for next-generation spintronic devices, yet achieving fully reversible and low-power voltage control of magnetization switching remains challenging. In this work, a quasi-nonvolatile and fully reversible electrical manipulation of perpendicular magnetic anisotropy is demonstrated in a horizontally-asymmetric Fe3GaTe2/CuInP2S6 van der Waals heterostructure at room temperature. By leveraging the in-plane migration and accumulation of Cu ions in CuInP2S6 under ultralow voltage pulses (0.9 V, ~16.66 kV/m), reversible modulation of the magnetic properties in the adjacent Fe3GaTe2 layer is achieved. Anomalous Hall effect and magneto-optical Kerr effect measurements confirm a cyclically stable modulation of the magnetic states, demonstrating a remarkably high voltage-controlled magnetic anisotropy coefficient (~1.0 × 106 fJ/V·m). Furthermore, it is demonstrated that the heterostructure, when integrated with spin-orbit torque devices, enables both voltage-controlled magnetic anisotropy and field-free switching of magnetization. This work provides a viable path toward energy-efficient two-dimensional spintronic devices.