# Fast domain walls governed by \OE rsted fields in cylindrical magnetic nanowires

## TL;DR

This paper demonstrates high-velocity current-induced domain wall motion in cylindrical magnetic nanowires, highlighting the crucial stabilizing role of Oersted fields in enabling fast, stable Bloch-point walls, advancing 3D data storage prospects.

## Contribution

It provides the first experimental evidence of domain wall dynamics in cylindrical nanowires and reveals the significant stabilizing effect of Oersted fields on Bloch-point walls.

## Key findings

- Domain walls reach velocities over 600 m/s in nanowires.
- Oersted fields are essential for stabilizing Bloch-point walls.
- Experimental results align with theoretical predictions.

## Abstract

Since its proposal, the idea to vastly increase data storage density with a magnetic non-volatile 3D shift-register has sustained interest in current-induced domain wall (DW) motion. So far, experimental efforts have focused on flat nanostrips, which exhibit a wide range of noteworthy effects, yet suffer from intrinsic DW instabilities limiting their mobility. In contrast, ferromagnetic cylindrical nanowires (NWs) can host a novel type of magnetic DW, namely the Bloch-point wall (BPW), which due to its specific 3D topology should not experience the same fundamental issue. This could give rise to DW velocities over ~1000 m/s and fascinating new physics including coupling to magnetic spin waves, however, experimental evidence of DW dynamics in NWs is lacking until now. Here we report experimental results on current-induced DW motion in NWs with velocities >600 m/s, quantitatively consistent with predictions. Furthermore, our results indicate that although previously disregarded, the OErsted field induced by the current plays instead a crucial and valuable role in stabilising exclusively BPWs.