Magnetic Moment Quenching and Spin Texture Formation at Pt/Co/Hf Interfaces

Abstract

Interfacial engineering in heavy metal/ferromagnet multilayers is a key approach for tailoring magnetic interactions for spintronic applications. Here, we investigate Pt/Co/Pt multilayers modified by ultrathin Hf spacer layers at the top Co interface. Magnetometry and X-ray magnetic circular dichroism (XMCD) reveal a strong reduction (up to ∼70%) in both the saturation magnetization and the Co atomic magnetic moment with increasing Hf thickness. XMCD further indicates proximity-induced moments in Pt and Hf with opposite alignment relative to Co. Magnetic force microscopy and scanning transmission X-ray microscopy show the formation of worm-like magnetic domains with thickness-dependent length scales. Micromagnetic simulations reproduce the observed domain patterns by introducing an effective Dzyaloshinskii–Moriya interaction, suggesting that interfacial asymmetry and magnetic moment quenching govern the magnetic configuration. These results show that buried spacer layers may provide a route for tuning magnetic properties relevant to spin transport and energy-efficient spintronic devices.