High-temperature series expansion for spin-1/2 Heisenberg models

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. Program summaryProgram Title: LCSEProgram Files doi:http://dx.doi.org/10.17632/vygxnfjt8b.1Licensing provisions: Apache-2.0.Programming language: C++11, MPI for parallelization, Mathematica for analysis of results.Nature of problem: Calculation of thermodynamic properties (mag- netic susceptibility and static structure factor) for quantum magnets on arbitrary lattices. A particularly hard problem pose quantum magnets on so frustrated lattice geometries, as they cannot be solved efficiently by Quantum Monte Carlo methods.Solution method: High-temperature series expansions employing a linked-cluster expansion allow to obtain a high-order series in the inverse temperature for thermodynamic quantities in the thermodynamic limit. The resulting high-temperature series are exact up to the expansion order. We implement the calculation of high-temperature series for the zero-field magnetic susceptibility and static magnetic structure factor for the spin-1/2 Heisenberg model on arbitrary infinite lattices in arbitrary dimension.External routines/libraries: ALPS [13,14], GMP [29]