Decoupled Cell Monte Carlo Method for Quantum Spin Systems
A decoupled cell method is proposed as a new method of Monte Carlo simulation for quantum spin systems. Thermodynamic quantities such as internal energy, in-plane and out-of-plane susceptibilities and spin pair correlation functions are calculated by this method in the 1D XY model. The results obtained agree well with the exact ones except for very low temperatures, indicating the validity of this method. Further application of this method strongly suggests (1) the existence of a phase transition in the quantum XY model on the square lattice similar to the Kosterlitz-Thouless transition in the classical XY model, and (2) the existence of a sublattice structure composed of three lattices which is short-ranged both spatially and temporally in the antiferromagnetic Heisenberg model on the triangular lattice.
KeywordsHigh Temperature Phase Triangular Lattice Monte Carlo Calculation Monte Carlo Step Spin Configuration
Unable to display preview. Download preview PDF.