Quantum phase transition in square- and triangular-lattice spin-½ antiferromagnets
Chen Zeng, I. Staples, R. F. Bishop
We use the coupled-cluster method to study ground-state properties of anisotropic $S=\frac{1}{2}$ antiferromagnets on square and triangular lattices, with the inclusion of arbitrarily long-ranged two-spin correlations. We detect the singularities of various quantities associated with the quantum phase transitions and also compute their critical exponents. The two-spin correlation coefficients for the triangular lattice are found to exhibit an interesting oscillatory behavior in their signs, knowledge of which could assist the implementation of quantum Monte Carlo simulations.
Physical review. B, Condensed matter•Apr 1, 1996•8 citations