Origin and tailoring of the antiferromagnetic domain structure in $\alpha$-Fe$_2$O$_3$ thin films unraveled by statistical analysis of dichroic spectro-microscopy (X-PEEM) images

TL;DR

This study uses statistical analysis of dichroic spectro-microscopy images to understand and control the magnetic domain structure in $ ext{Fe}_2 ext{O}_3$ thin films, revealing inheritance from precursor layers and invariance with thickness.

Contribution

It uncovers the inheritance of antiferromagnetic domain structures from ferrimagnetic precursor layers and demonstrates how to tune these structures through precursor modifications.

Findings

Domain structure is invariant with film thickness.

Antiferromagnetic domains inherit from ferrimagnetic precursor layers.

Modifying precursor layers alters the final antiferromagnetic domain structure.

Abstract

The magnetic microstructure and domain wall distribution of antiferromagnetic $\alpha$-Fe$_2$O$_3$ epitaxial layers is determined by statistical image analyses. Using dichroic spectro-microscopy images, we demonstrate that the domain structure is statistically invariant with thickness and that the antiferromagnetic domain structure of the thin films is inherited from the ferrimagnetic precursor layer one, even after complete transformation into antiferromagnetic $\alpha$-Fe$_2$O$_3$. We show that modifying the magnetic domain structure of the precursor layer is a genuine way to tune the magnetic domain structure and domain walls of the antiferromagnetic layers.