Deterministic Spin-Orbit Torque Switching in 2D Dilute Magnetic Semiconductors Above Room Temperature

Two-dimensional (2D) van der Waals (vdW) magnets with perpendicular magnetic anisotropy (PMA) hold great potential for next-generation high-density, energy-efficient spintronics^1–9. Recent breakthroughs have emerged with the discovery of Fe₃GaTe₂ ,PtTe₂ and CrTe₂, boasting Tc exceeding 300K, opening possibilities for constructing functional 2D magnetic devices operating at room temperature^10–14. However, achieving high-efficiency spin-orbit torque (SOT) switching of monolayer vdW magnets at room temperature poses a significant challenge, particularly in the absence of an external magnetic field. Here we demonstrate an ultra-low power, field-free, deterministic, and nonvolatile PMA switching of SOT system up to 370 K using a dilute magnetic semiconductor (DMS), monolayer Fe:MoS₂¹⁵, through interfacial spin-orbit coupling with a Pt Hall bar. A clear anomalous Hall effect (AHE) loop shift is observed at a zero in-plane magnetic field, verifying the existence of z spins in the Fe:MoS₂/Pt heterostructure, which induces a damping-like torque that facilitates field-free SOT switching with the current density of 10⁵ A cm⁻² at 370K. The Fe doping into MoS₂ disintegrates the rotational crystal symmetry, evidenced by the crystal axis dependency of the switching in Fe:MoS₂/Pt heterostructures with PMA. A strong topological Hall effect (THE) was also observed, attributed to interfacial Dzyaloshinskii-Moriya interaction (DMI). This field-free SOT application using a 2D monolayer dilute magnetic semiconductor provides a new pathway for developing highly power-efficient spintronic devices.

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