Domain walls are the interfaces between domains with different magnetic orientation. They carry essential information on the magnetic nanostructure and can have distinct topological properties. Despite wide research on magnetic domains, the study and direct control of individual domain walls remain challenging due to the need for extremely pure materials and very specific experimental protocols.

Using Chromium Oxide (Cr2O3) and Scanning NV Magnetometry, the group led by Prof. Patrick Maletinksy (Quantum Sensing Lab, University of Basel) unveiled for the first time the nanoscale mechanics of antiferromagnetic domain walls.

The team managed to nucleate domain walls in otherwise monodomain Cr2O3 samples by applying external electric and magnetic fields. They used engineered nanoscale mesas as pinning centers for Domain Walls, and laser-dragging techniques to move the domain walls. Thanks to the extremely high spatial resolution and sensitivity of Scanning NV Magnetometry, they quantitatively characterized the domain walls through their weak uncompensated magnetic moments.

These results demonstrate the possibility to switch and read bits of nanoscale dimensions using Scanning NV Magnetometry and laser-dragging. They suggest novel architectures for Domain Wall-based antiferromagnetic memories and new approaches to antiferromagnetic spintronics.

Check out the Nature Physics paper published in March 2021.