Room-temperature two-dimensional multiferroic metal with voltage-controllable magnetic order.

Realizing two-dimensional multiferroics with robust magnetoelectric coupling for electric-field-controlled magnetism at room temperature poses substantial challenges, as ferroelectricity and magnetism inherently conflict. Here we report air-stable bilayer CrTe2 that exhibits intrinsic room-temperature multiferroicity. Structural and magnetic characterization reveals an alternating ferromagnetic and antiferromagnetic bilayer architecture, driven by interlayer charge transfer that spontaneously breaks inversion symmetry and generates a switchable out-of-plane ferroelectric polarization. Scanning probe microscopy confirms the non-volatile control of magnetization states with an electric field, enabling electrical writing and magnetic reading functionalities. This mechanism, rooted in interlayer charge transfer, rather than conventional spin-orbit coupling, provides a foundation for engineering multiferroics with layered systems. The demonstration of a two-dimensional multiferroic material with magnetoelectric coupling under ambient conditions provides opportunities for energy-efficient memory devices and quantum sensing technologies.