Vertex dynamics in finite two dimensional square spin ices

TL;DR

This paper investigates the dynamics of local magnetic ordering in artificial square spin ices, emphasizing the role of geometrical frustration, vertex configurations, and long-range interactions in their evolution towards steady states.

Contribution

It introduces a vertex configuration-based particle picture and a mean field model to analyze finite size effects and dynamic behaviors in square spin ices.

Findings

Vertex processes predict different behaviors for open and closed edges.

Numerical simulations confirm the importance of correlations and long-range interactions.

Mean field model provides insights into finite size effects.

Abstract

Local magnetic ordering in artificial spin ices is discussed from the point of view of how geometrical frustration controls dynamics and the approach to steady state. We discuss the possibility of using a particle picture based on vertex configurations to interpret time evolution of magnetic configurations. Analysis of possible vertex processes allows us to anticipate different behaviors for open and closed edges and the existence of different field regimes. Numerical simulations confirm these results and also demonstrate the importance of correlations and long range interactions in understanding particle population evolution. We also show that a mean field model of vertex dynamics gives important insights into finite size effects.