[8p-N304-1~9] 10.1 Emerging materials in spintronics and magnetics (including fabrication and characterization methodologies)

1:45 PM - 2:00 PM JST(4:45 AM - 5:00 AM UTC)English Presentation

[8p-N304-2] Orbital Torque and Field-Free Magnetization Switching in a Light-Element-Based SOT Device

〇(P)GAURAV KUMAR SHUKLA¹, SHINJI ISOGAMI¹ (1.National Institute for Materials Science (NIMS), Tsukuba 305-0047, Japan)

Keywords:

Spin-orbit torque,Magnetic memory device,Light metal systems

Orbital torque from the orbital Hall effect (OHE) offers a promising route for next-generation, energy-efficient orbitronic devices. While conventional spin-orbit torque (SOT) devices rely on heavy metals, their scarcity motivates exploration of light-element-based alternatives. Recent studies show that light metals can generate significant orbital currents, which convert into spin currents in adjacent ferromagnets. Inspired by Cr₂N-based 2D-MXene systems exhibiting field-free switching (FFS), we demonstrate FFS in a VN-based SOT device: Al₂O₃//VN(5)/[Co(0.35)/Pt(0.3)]₃/MgO(3) (in nm). Full magnetization switching observed under in-plane fields and partial switching occurs at zero field. Second harmonic Hall measurements reveal that [Co/Pt]₃ shows twice the torque efficiency of CoFeB, while Py shows negligible effect attributed to orbital to spin conversion efficiency. FFS is attributed to broken mirror symmetry from in-plane magnetic anisotropy.