# Imaging the stochastic microstructure and dynamic development of correlations in perpendicular artificial spin ice

## TL;DR

This study employs magneto-optical Kerr microscopy to analyze the microstates and correlations in perpendicular artificial spin ice, revealing how interaction strength, disorder, and stochasticity influence magnetization switching behavior.

## Contribution

It introduces a method to track microstates in artificial spin ice and uncovers the stochastic nature of microstate evolution during hysteresis cycles.

## Key findings

- Nearest neighbor correlations depend on interaction strength and disorder.
- Global hysteresis characteristics are repeatable, microstates are stochastic.
- Individual island behavior varies between runs.

## Abstract

We use spatially resolved magneto-optical Kerr microscopy to track the complete microstates of arrays of perpendicular anisotropy nanomagnets during magnetization hysteresis cycles. These measurements allow us to disentangle the intertwined effects of nearest neighbor interaction, disorder, and stochasticity on magnetization switching. We find that the nearest neighbor correlations depend on both interaction strength and disorder. We also find that although the global characteristics of the hysteretic switching are repeatable, the exact microstate sampled is stochastic with the behavior of individual islands varying between nonminally identical runs.