Chiral Coupling between Magnetic Layers with Orthogonal Magnetization

TL;DR

This paper demonstrates strong chiral interlayer Dzyaloshinskii-Moriya interaction between in-plane and perpendicular magnetic layers mediated by a platinum spacer, revealing potential for spintronic device design.

Contribution

It uncovers the role of Pt in mediating interlayer DMI between orthogonal magnetic layers, a novel insight for chiral magnetic coupling.

Findings

Pt spacer induces significant DMI with effective fields up to 15 mT.

DMI strength decreases with increasing Pt thickness.

Other spacers like Ru, Ta, Ti induce weaker coupling.

Abstract

We report on the occurrence of strong interlayer Dzyaloshinskii-Moriya interaction (DMI) between an in-plane magnetized Co layer and a perpendicularly magnetized TbFe layer through a Pt spacer. The DMI causes a chiral coupling that favors one-handed orthogonal magnetic configurations of Co and TbFe, which we reveal through Hall effect and magnetoresistance measurements. The DMI coupling mediated by Pt causes effective magnetic fields on either layer of up to 10-15 mT, which decrease monotonously with increasing Pt thickness. Ru, Ta, and Ti spacers mediate a significantly smaller coupling compared to Pt, highlighting the essential role of Pt in inducing the interlayer DMI. These results are relevant to understand and maximize the interlayer coupling induced by the DMI as well as to design spintronic devices with chiral spin textures.