Magnetization dynamics of a CrO$_2$ grain studied by micro-Hall magnetometry

TL;DR

This study uses micro-Hall magnetometry to investigate the magnetization dynamics of a single CrO$_2$ grain, revealing domain wall motion, imperfections, and Barkhausen jumps through experimental and simulation methods.

Contribution

It demonstrates the application of micro-Hall magnetometry to analyze domain wall behavior and imperfections in a single micron-sized CrO$_2$ grain.

Findings

Identification of domain wall motion and pinning sites.

Observation of Barkhausen jumps during magnetization reversal.

Correlation of experimental results with micromagnetic simulations.

Abstract

Micro-Hall magnetometry is employed to study the magnetization dynamics of a single, micron-size CrO$_2$ grain. With this technique we track the motion of a single domain wall, which allows us to probe the distribution of imperfections throughout the material. An external magnetic field along the grain's easy magnetization direction induces magnetization reversal, giving rise to a series of sharp jumps in magnetization. Supported by micromagnetic simulations, we identify the transition to a state with a single cross-tie domain wall, where pinning/depinning of the wall results in stochastic Barkhausen jumps.