Magnetic Proximity Effect and Anomalous Hall Effect in Pt/Y3Fe5−xAlxO12 Heterostructures

Understanding the structural origin of the magnetic proximity effect (MPE) at the interface of Pt and Y${}_{3}$Fe${}_{5}$O${}_{12}$ (YIG) is critical to developing YIG-based spintronic devices. This work reveals that the MPE mechanism at this interface is due to band hybridization and exchange coupling between tetrahedral Fe${}^{3+}$ ions and Pt atoms. Controlled substitution of nonmagnetic Al${}^{3+}$ for Fe${}^{3+}$ in YIG's tetrahedral lattice is the key to these experiments. MPE depends linearly on the concentration of tetrahedral Fe${}^{3+}$ in YIG and plays the main part in the anomalous Hall effect at lower temperatures, while at higher temperatures the spin Hall effect is dominant.