Berezinskii–Kosterlitz–Thouless phase transition of 2D dilute generalized XYXY model

The Berezinskii–Kosterlitz–Thouless (BKT) phase transition of 2D dilute generalized XYXY model on a triangular lattice is studied by a hybrid Monte Carlo (MC) method. The critical temperatures are obtained by several methods for dilute and non-dilute cases. It is found that the critical temperature decreases with increasing non-magnetic occupation density ρρ and the BKT phase transition vanishes when the magnetic occupation density reaches the site percolation threshold: ρmag=pc=0.5ρmag=pc=0.5. Some thermodynamic quantities are also discussed.