Interfacial alloying contributions to the magnetic proximity effect in Pt/dysprosium iron garnet
Phys. Rev. B 112, 054433 – Published 13 August, 2025
DOI: https://doi.org/10.1103/7jdl-hkpp
Abstract
The magnetic proximity effect (MPE), which describes a magnetic response from a heavy metal layer as a result of an adjacent magnetic layer, plays an important role in the behavior of heavy-metal/ferro- or ferrimagnet thin film heterostructures. However, in the case of heavy-metal/rare-earth iron garnet bilayers, the presence and magnitude of the MPE has been debated. We previously reported an MPE in a Pt/dysprosium iron garnet (DyIG) heterostructure where the two layers were grown without breaking vacuum, finding that the magnetic moment present in the Pt layer scales with the magnitude of the DyIG moment and varies nonmonotonically through the DyIG compensation temperature. However, the origin of the magnetic signal from the Pt layer was not identified. In contrast, Pt/DyIG grown with a vacuum break did not exhibit an MPE. Here we investigate the origin of the magnetic moment in the Pt layer using x-ray absorption spectroscopy, x-ray circular dichroism, composition mapping, and simulations of ion bombardment. The results are consistent with the presence of an intermixed Fe-Dy-Pt interfacial alloy layer formed during the growth of the Pt on the DyIG resulting in a measurable MPE.
