Ionic Modulation of Interfacial Magnetism through Electrostatic Doping in Pt/YIG bilayer heterostructure

TL;DR

This paper demonstrates voltage-induced modulation of interfacial magnetism in YIG/Pt heterostructures, achieving significant FMR shifts through ionic electrostatic doping, advancing voltage-tunable spintronic devices.

Contribution

It introduces ionic electrostatic doping as a method to control interfacial magnetism in YIG/Pt bilayers, with both experimental and theoretical insights into the mechanism.

Findings

Achieved 690 Oe FMR shift with 4.5 V bias.

Voltage induces extra ferromagnetic ordering in Pt layer.

Theoretical simulation shows Pt5+ ions contribute to magnetic ordering.

Abstract

Voltage modulation of yttrium iron garnet (YIG) with compactness, high speed response, energy efficiency and both practical/theoretical siginificances can be widely applied to various YIG based spintronics such as spin Hall, spin pumping, spin Seeback effects. Here we initial an ionic modulation of interfacial magnetism process on YIG/Pt bilayer heterostructures, where the Pt capping would influence the ferromagnetic (FMR) field position significantly, and realize a significant magnetism enhancement in bilayer system. A large voltage induced FMR field shifts of 690 Oe has been achieved in YIG (13 nm)/Pt (3 nm) multilayer heterostructures under a small voltage bias of 4.5 V. The remarkable ME tunability comes from voltage induced extra FM ordering in Pt metal layer near the Pt/YIG interface. The first-principle theoretical simulation reveal that the electrostatic doping induced Pt5+ ions have strong magnetic ordering due to uncompensated d orbit electrons. The large voltage control of FMR change pave a foundation towards novel voltage tunable YIG based spintronics.