1PA25 双二次型相互作用をもつANNNXYモデルの相図

抄録

The phase transition of axial next nearest neighbour XY model with biquadratic interaction is studied to clarify the crossover from the XYmodel to Ising model, in which phases with wave number q=0,1/4,1/5, and 1/6 are taken into account and phase diagrams at finite temperature are shown.