Adjustable 3D magnetic configuration in ferrimagnetic multilayers with competing interactions visualized by soft X-ray vector tomography

TL;DR

This study employs soft X-ray vector tomography to visualize and analyze the 3D magnetic configurations in ferrimagnetic multilayers, revealing tunable magnetic structures influenced by composition and fabrication parameters.

Contribution

It demonstrates the use of 3D magnetic visualization to understand and control complex magnetic interactions in multilayered ferrimagnetic materials.

Findings

Visualization of chevron-patterned stripe domains in multilayers

Observation of exchange springs and vortex structures

Tuning of exchange spring strength via composition and anisotropy

Abstract

Soft X-ray magnetic vector tomography has been used to visualize with unprecedented detail and solely from experimental data the 3D magnetic configuration of a ferrimagnetic Gd12Co88/Nd17Co83/Gd24Co76 multilayer with competing anisotropy, exchange and magnetostatic interactions at different depths. The trilayer displays magnetic stripe domains, arranged in a chevron pattern, which are imprinted from the central Nd17Co83 into the bottom Gd12Co88 layer with a distorted closure domain structure across the thickness. Near the top Gd24Co76 layer, local exchange springs with out-of-plane magnetization reversal, modulated ripple patterns and magnetic vortices and antivortices across the thickness are observed. The detailed analysis of the magnetic tomogram shows that the effective strength of the exchange spring at the NdCo/GdCo interface can be finely tuned by GdxCo1-x composition and anisotropy (determined by sample fabrication) and in-plane stripe orientation (adjustable), demonstrating the capability of 3D magnetic visualization techniques in magnetic engineering research.