Finite-size scaling analysis of the critical behavior of the Baxter–Wu model

We use the recently developed critical minimum energy subspace (CrMES) approximation scheme to study the critical behavior of the Baxter–Wu model. This scheme uses only a properly determined part of the energy spectrum and allows us to obtain high accuracy for relatively large systems with considerably reduced computational effort. The density of states is constructed by a multi-range Wang–Landau sampling and from this we obtain the critical properties of specific heat and of the “reduced Binder cummulant”. The good agreement of our results with existing exact solutions demonstrates the accuracy of our approximation technique.