Reweighting histogram technique for the quantum Heisenberg ferromagnet Original Research Article

In this work, we extend the reweighting histogram technique (RHT) to make it suitable for the study of quantum spin systems. Combining the Handscomb quantum Monte Carlo method with RHT, we compute some equilibrium critical parameters for the quantum S=1/2 Heisenberg ferromagnet on simple cubic lattices of sizes up to L=48. We found kBTc/J=1.67764(2), U∗=0.4504(1), γ=1.397(20), β=0.360(6) and ν=0.705(10). These are in perfect agreement with the best field theory and high temperature series results. Also, we found that the auto-correlation time near criticality scales roughly with the systemʹs volume. Potential applications of the method to the study of general quantum spin systems are discussed.