Enhancing Perpendicular Magnetic Anisotropy in Garnet Ferrimagnet by Interfacing with Few-Layer WTe2

TL;DR

This paper demonstrates that interfacing garnet ferrimagnet YIG with few-layer WTe2 induces perpendicular magnetic anisotropy and enhances damping, offering new avenues for spintronic device engineering.

Contribution

It reports the novel induction of perpendicular magnetic anisotropy in YIG via WTe2 interface, independent of WTe2 thickness, advancing magnetic memory technology.

Findings

WTe2 induces perpendicular magnetic anisotropy in YIG.

Enhanced Gilbert damping observed with WTe2 coverage.

Interface effects are thickness-independent down to single quadruple-layer.

Abstract

Engineering magnetic anisotropy in a ferro- or ferrimagnetic (FM) thin film is crucial in spintronic device. One way to modify the magnetic anisotropy is through the surface of the FM thin film. Here, we report the emergence of a perpendicular magnetic anisotropy (PMA) induced by interfacial interactions in a heterostructure comprised of a garnet ferrimagnet, Y3Fe5O12 (YIG), and the low-symmetry, high spin orbit coupling (SOC) transition metal dichalcogenide, WTe2. At the same time, we also observed an enhancement in Gilbert damping in the WTe2 covered YIG area. Both the magnitude of interface-induced PMA and the Gilbert damping enhancement have no observable WTe2 thickness dependence down to single quadruple-layer, indicating that the interfacial interaction plays a critical role. The ability of WTe2 to enhance the PMA in FM thin film, combined with its previously reported capability to generate out-of-plane damping like spin torque, makes it desirable for magnetic memory applications.