We investigate the temperature dependence of the order parameters of the Blume–Capel model for zero magnetic field in the lowest approximation of the cluster variation method which is identical to the mean-field approximation. Besides the stable branches of the order parameters, we establish...

The temperature dependence of the magnetization and quadrupole order parameters of the Blume–Emery–Griffiths (BEG) model Hamiltonian with the nearest-neighbor ferromagnetic exchange interactions [both bilinear (J) and biquadratic (K)] and crystal field interaction (D) is studied using the...