# Order and Disorder in the Magnetisation of the Chiral Crystal CrNb$_3$S$_6$

## TL;DR

This paper investigates the phase transitions and magnetic configurations in the chiral crystal CrNb$_3$S$_6$, revealing how dislocations influence the formation of chiral soliton lattices and their magnetic properties.

## Contribution

It provides a detailed experimental and theoretical analysis of the transition mechanisms between magnetic phases in CrNb$_3$S$_6$, highlighting the role of dislocations and sample morphology.

## Key findings

- Dislocations mediate the formation of CSL and F-FM regions.
- Sample size and shape influence magnetic properties and dislocation behavior.
- Magnetic fields can stabilize and modify dislocations beyond uniform film predictions.

## Abstract

Competing magnetic anisotropies in chiral crystals with Dzyaloshinskii Moriya exchange interactions can give rise to non-trivial chiral topological magnetisation configurations with new and interesting properties. One such configuration is the magnetic soliton, where the moment continuously rotates about an axis. This magnetic system can be considered to be one dimensional and, because of this, it supports a macroscale coherent magnetisation, giving rise to a tunable chiral soliton lattice (CSL) that is of potential use in a number of applications in nanomagnetism and spintronics. In this work we characterise the transitions between the forced-ferromagnetic (F-FM) phase and the CSL one in CrNb$_3$S$_6$ using differential phase contrast imaging in a scanning transmission electron microscope, conventional Fresnel imaging, ferromagnetic resonance spectroscopy, and mean-field modelling. We find that the formation and movement of dislocations mediate the formation of CSL and F-FM regions and that these strongly influence the highly hysteretic static and dynamic properties of the system. Sample size and morphology can be used to tailor the properties of the system and, with the application of magnetic field, to locate and stabalise normally unstable dislocations and modify their dimensions and magnetic configurations in ways beyond that predicted to occur in uniform films.