SPIN-1/2 TWO-DIMENSIONAL ANISOTROPIC HEISENBERG ANTIFERROMAGNETS

摘要: A real space renormalization group method is applied to study the spin-1/2 two-dimensional anisotropic Heisenberg antiferromagnets. We carry out calculation on a 5×5 cluster by using variational approach. The ground-state energy per site estimated as e0=−0.6845±0.0005 which in good agreement with other numerical estimates. also calculate different ground state energies when anisotropy changes. By comparing 3×3 resulting threshold for long range order drops and curve of parameter vs. shows no hint discontinuity over wide parameters. Hence, our suggests that long-range exists antiferromagnets two dimensions.