Proximity-induced magnetism and the enhancement of damping in ferromagnetic/heavy metal systems

The relationship between proximity-induced magnetism (PIM) at the heavy metal/ferromagnet interface and spin-transport across such interfaces has generated significant debate. To investigate the link between the two, element specific x-ray magnetic circular dichroism and ferromagnetic resonance measurements were made on the same CoFe/Au/Pt and NiFe/Au/Pt thin film samples with varying Au thickness, with complementary SIMS analysis, which shows evidence of Ni diffusion from NiFe into the Pt. An approximately linear relationship is observed between the magnitude of Pt PIM and magnitude of damping enhancement in both systems. The results demonstrate that electronic hybridization of the heavy metal and ferromagnet is required for a full understanding of damping enhancement and interfacial spin-transport for spintronic devices.

Automated summary

The relationship between proximity-induced magnetism at the heavy metal/ferromagnet interface and spin-transport has been investigated through element specific x-ray magnetic circular dichroism and ferromagnetic resonance measurements on CoFe/Au/Pt and NiFe/Au/Pt thin film samples. The results show a linear relationship between the magnitude of Pt PIM and damping enhancement in both systems, indicating that electronic hybridization of the heavy metal and ferromagnet is essential for understanding damping enhancement and interfacial spin-transport for spintronic devices.