Strange relaxation and metastable behaviours of the Ising ferromagnetic thick cubic shell

TL;DR

This study investigates how the thickness of a cubic ferromagnetic shell influences its equilibrium and nonequilibrium magnetic behaviors, revealing a hyperbolic tangent relation for critical temperature and non-monotonic metastable lifetime variations.

Contribution

It provides new insights into the dependence of phase transition and metastability on shell thickness in Ising ferromagnetic systems using Monte Carlo simulations.

Findings

Critical temperature increases with thickness following a hyperbolic tangent relation.

Relaxation time decreases with increasing thickness, showing three regimes.

Metastable lifetime varies non-monotonically with thickness, with a maximum at a specific value.

Abstract

We have studied the equilibrium and nonequilibrium behaviours of the Ising ferromagnetic thick cubic shell by Monte Carlo simulation. Our goal is to find the dependence of the responses on the thickness of the shell. In the equilibrium results, we found that the pseudo-critical temperature of ferro-para phase transition of thick cubic shell increases with the increase of the thickness following a hyperbolic tangent relation. In the nonequilibrium studies, the relaxation time has been found to decrease with the increase of the thickness of the cubic shell. Here three different regimes are found, namely rapid fall, plateau and linear region. The metastable behaviour has been studied also as another kind of non-equilibrium response. The metastable lifetime has been studied as function of the thickness of the cubic shell. A non-monotonic variation of metastable lifetime with the thickness of the shell is observed. A specified thickness for longest-lived metastability has been identified.