Spin-2 antiferromagnetic-ferromagnetic Blume-Capel model with random distribution on the Bethe lattice

The phase diagrams of antiferromagnetic (AFM)-ferromagnetic (FM) spin-2 Blume-Capel (BC) model with random distribution of bilinear exchange interaction parameters (J) for given probabilities (P) were considered on Bethe lattice (BL) by using exact recursion relations. The BL is partitioned into two sublattices to account for AFM interactions by adding the effects of external magnetic field (H). The model is examined for coordination number of four, which is equivalent to square lattice with the crystal field (D) present. It is a complete model,i.e. it corresponds to AFM, FM, or mixed AFM-FM models, respectively, when P is taken one, zero, or any value in between. By considering the thermal variations of sublattice magnetizations, the phase diagrams were obtained on (Formula presented.) and (Formula presented.) planes for given values of D and H, respectively. It is found that the model gives both second- and first-order phase transitions, reentrant behavior, and few critical points.