Monte Carlo study of the magnetic properties of spin liquid compound NiGa₂S₄

The magnetic properties of two-dimensional antiferromagnet NiGa₂S₄ have attracted much attention and yet some problems are far from being solved. We investigate the magnetic properties of NiGa₂S₄ by Monte Carlo simulations. A new spin-interacting model is proposed to describe the system, and the specific heat together with the doping effect of nonmagnetic impurity is studied by simulations. The double peaks of the specific heat as well as other behaviors are well reproduced. We also compare our results with those of other models, and the underlying physics is discussed.