Magnetic Switching in Monolayer 2D Diluted Magnetic Semiconductors via Spin-to-Spin Conversion

The integration of 2D van der Waals (vdW) magnets with topological insulators or heavy metals holds great potential for realizing next-generation spintronic memory devices. However, achieving high-efficiency spin–orbit torque (SOT) switching of monolayer vdW magnets at room temperature poses a significant challenge, particularly without an external magnetic field. Here, it is shown field-free, deterministic, and nonvolatile SOT switching of perpendicular magnetization in the monolayer, diluted magnetic semiconductor (DMS), Fe-doped MoS₂ (Fe:MoS₂) at up to 380 K with a current density of ≈7 × 10⁴ A cm⁻². The in situ doping of Fe into monolayer MoS₂ via chemical vapor deposition and the geometry-induced strain in the crystal break the rotational switching symmetry in Fe:MoS₂, promoting field-free SOT switching by generating out-of-plane spins via spin-to-spin conversion. An apparent anomalous Hall effect (AHE) loop shift at a zero in-plane magnetic field verifies the existence of z spins in Fe:MoS₂, inducing an antidamping-like torque that facilitates field-free SOT switching. This field-free SOT application using a 2D ferromagnetic monolayer provides a new pathway for developing highly power-efficient spintronic memory devices.