Phase diagram of a three-dimensional dipolar model on a FCC lattice

TL;DR

This study maps the magnetic phase diagram of a 3D dipolar model on an FCC lattice, revealing various magnetic phases influenced by uniaxial anisotropy and disorder, using tempered Monte Carlo simulations.

Contribution

It provides the first detailed phase diagram of a dipolar FCC lattice model with uniaxial anisotropy and disorder, relevant for magnetic nanoparticle supracrystals.

Findings

Identified paramagnetic, ferromagnetic, quasi long-range ordered ferromagnetic, and spin-glass phases.

Demonstrated how uniaxial anisotropy influences phase boundaries.

Mapped the phase diagram in the temperature and anisotropy strength plane.

Abstract

The magnetic phase diagram at zero external field of an ensemble of dipoles with uniaxial anisotropy on a FCC lattice is investigated from tempered Monte Carlo simulations. The uniaxial anisotropy is characterized by a random distribution of easy axes and its magnitude $\lambda_u$ is the driving force of disorder and consequently frustration. The phase diagram, separating the paramagnetic, ferromagnetic, quasi long range ordered ferromagnetic and spin-glass regions is thus considered in the temperature, $\lambda_u$ plane. This system is aimed at modeling the magnetic phase diagram of supracrystals of magnetic nanoparticles.