Modified self-consistent harmonic approximation and its application to two-dimensional easy-axis quantum ferromagnets

TL;DR

This paper introduces a modified self-consistent harmonic approximation tailored for quantum S=1 systems and demonstrates its effectiveness on two-dimensional easy-axis quantum ferromagnets, aligning well with established simulation methods.

Contribution

The paper presents a novel modification of the self-consistent harmonic approximation specifically for quantum S=1 systems, improving its applicability and accuracy.

Findings

Results agree with Monte-Carlo simulations

Matches pure-quantum SCHA results

Offers advantages over traditional SCHA

Abstract

In the paper we describe the modification of self-consistent harmonic approximation for quantum S=1 systems. This method has a number of advantages in comparison with usual SCHA. We apply the method to two-dimensional ferromagnets with easy-axis exchange or single-site anisotropy. The results are in good agreement with Monte-Carlo simulations and pure-quantum SCHA.