Finite temperature phase diagram of ultrathin magnetic films without external fields

TL;DR

This paper develops a mean field theory for ultrathin magnetic films at finite temperatures, compares it with Monte Carlo simulations, and explores stripe patterns and ground state connections.

Contribution

It introduces a mean field approach valid near the Spin Reorientation Transition and links finite temperature behavior with ground state properties.

Findings

Mean field theory agrees with Monte Carlo simulations in low anisotropy regime.

Identifies canted states and stripe width variations at finite temperatures.

Establishes connections between finite temperature phases and ground state configurations.

Abstract

We analyze the finite temperature phase diagram of ultrathin magnetic films by introducing a mean field theory, valid in the low anisotropy regime, i.e., close to de Spin Reorientation Transition. The theoretical results are compared with Monte Carlo simulations carried out on a microscopic Heisenberg model. Connections between the finite temperature behavior and the ground state properties of the system are established. Several properties of the stripes pattern, such as the presence of canted states, the stripes width variation phenomenon and the associated magnetization profiles are also analyzed.