High-Temperature Series Expansion for Spin-1/2 Heisenberg Models

TL;DR

This paper introduces a computational method for high-temperature series expansion of spin-1/2 Heisenberg models on various lattices, enabling analysis of magnetic properties and extraction of coupling constants from experimental data.

Contribution

It provides a versatile high-temperature series expansion code applicable to arbitrary lattices, demonstrated on an anisotropic triangular lattice, with practical extraction of model parameters from experiments.

Findings

Series expansion up to 12th order for susceptibility

Series expansion up to 10th order for structure factor

Effective coupling constants derived from experimental data

Abstract

We present a high-temperature series expansion code for spin-1/2 Heisenberg models on arbitrary lattices. As an example we demonstrate how to use the application for an anisotropic triangular lattice with two independent couplings J1 and J2 and calculate the high-temperature series of the magnetic susceptibility and the static structure factor up to 12th and 10th order, respectively. We show how to extract effective coupling constants for the triangular Heisenberg model from experimental data on Cs2CuBr4.