Spin-1 Blume–Capel model with longitudinal random crystaland transverse magnetic fields：a mean-field approach

The spin-1 Blume-Capel model with transverse Ω and longitudinal external magnetic fields h in addition to a longitudinal random crystal field D is studied in the mean-field approximation. It is assumed that the crystal field is either turned on with probability p or turned off with probability 1-p on the sites of a square lattice. Then the phase diagrams are calculated on the reduced temperature-crystal field planes for given values of γ=Ω/J and p at zero h. Thus, the effect of changing γ and p are illustrated on the phase diagrams in a great detail and interesting results are observed.