# Intermediate phase and pseudo phase transition in an artificial spin ice model

## TL;DR

This study uses Monte Carlo simulations to explore the phase transitions and magnetic monopole excitations in a controllable artificial spin ice system, revealing an intermediate phase and pseudo phase transition in finite systems.

## Contribution

It introduces the concept of an intermediate phase and pseudo phase transition in a specific artificial spin ice model, highlighting finite-size effects and monopole-like excitations.

## Key findings

- Existence of a single phase transition in the thermodynamic limit.
- Emergence of an intermediate phase with magnetic domains in finite systems.
- Identification of two types of monopole-like low energy excitations.

## Abstract

In this paper we conduct Monte Carlo simulations to investigate the thermodynamic properties of a geometry of artificial spin ice recently proposed in the literature that had been termed "rewritable" spin ice, for its experimental realization allows total control over the microstates of the system. Our results show that in the thermodynamic limit a single phase transition between a fully magnetized state and a paramagnetic state exists, whereas for finite systems an intermediate phase also emerges, engendering a low temperature pseudo phase transition. This intermediate phase is characterized by large magnetic domains separated by domain walls composed of monopole-like excitations, resulting in low net magnetization values. We also show that two types of low energy excitations that behave as magnetic monopoles emerge in the system, both of which are geometrically constrained to move along a predefined path.