Magnetic response of the J1-J2 spin Hamiltonian from classical Monte Carlo and Schwinger boson mean field theory

TL;DR

This study investigates the magnetic susceptibilities of the J1-J2 spin Hamiltonian using classical Monte Carlo and Schwinger boson mean field theories, revealing linear temperature dependence in susceptibility away from criticality.

Contribution

It compares classical Monte Carlo and Schwinger boson mean field approaches to analyze magnetic responses in the J1-J2 model across a range of parameters.

Findings

Linear-T susceptibility behavior observed away from critical point

Susceptibility window narrows near the critical point

Consistent results between the two theoretical methods

Abstract

Magnetic susceptibilities at several potential ordering wave vectors (0,0), (\pi,0), and (\pi,\pi) are analyzed for the antiferromagnetic J1-J2 spin Hamiltonian by classical Monte Carlo and Schwinger boson mean field theories over the parameter range 0 \le 2J_2/J_1 \le 2. We find a nearly linear-T behavior of the uniform susceptibility that extends up to the temperature scale of J_1 within both calculation schemes when 2J_2/J_1 is sufficiently removed from the critical point 2J_2/J_1=1. The window of linear temperature dependence diminishes as the critical point is approached.