Slow dynamics in a 2D Ising model with competing interactions

TL;DR

This study uses Monte Carlo simulations to analyze slow, metastability-influenced dynamics in a 2D Ising model with competing interactions, relevant to ultra-thin magnetic films at low temperatures.

Contribution

It demonstrates how metastable states cause slow domain growth dynamics in a 2D Ising model with competing exchange and dipolar interactions.

Findings

Metastable states block domain growth, slowing dynamics.

Slow dynamics are linked to metastability in the phase diagram.

Results are relevant for understanding magnetic film behavior.

Abstract

The far-from-equilibrium low-temperature dynamics of ultra-thin magnetic films is analyzed by using Monte Carlo numerical simulations on a two dimensional Ising model with competing exchange ($J_0$) and dipolar ($J_d$) interactions. In particular, we focus our attention on the low temperature region of the $(\delta,T)$ phase diagram (where $\delta= J_0/J_d$) for the range of values of $\delta$ where striped phases with widths $h=1$ ($h1$) and $h=2$ ($h2$) are present. The presence of metastable states of the phase $h2$ in the region where the phase $h1$ is the thermodynamically stable one and viceversa was established recently. In this work we show that the presence of these metastable states appears as a blocking mechanism that slows the dynamics of magnetic domains growth when the system is quenched from a high temperature state to a low temperature state in the region of metastability.