Phase diagrams of the kinetic metamagnetic spin‐3/2 Blume–Capel model in an oscillating external field

Dynamic phase diagrams are calculated, within a mean‐field approach, for the kinetic metamagnetic spin‐3/2 Blume–Capel model in the presence of a time‐dependent oscillating external magnetic field using Glauber‐type stochastic dynamics and six fundamental types of phase diagrams are found in the reduced temperature ( T ) and magnetic‐field amplitude parameter ( h ) plane. The phase diagrams exhibit one, two or three dynamic tricritical points, and besides the paramagnetic (P), the antiferromagnetic‐3/2 (AF 3/2 ), the antiferromagnetic‐1/2 (AF 1/2 ) phases, three coexistence phase regions, namely AF 3/2 + P, AF 1/2 + P, AF 3/2 + AF 1/2 , exist depending upon the interaction parameters. The dynamic phase boundaries between the P and AF 3/2 phases are always second‐order lines, but between the P and AF 1/2 phases are second‐ or/and first‐order lines. All other dynamic phase boundaries among the disordered, ordered phases and coexistence phase regions are first‐order lines. We have investigated the influence of the crystal field interaction ( D ) and we obtain five different phase diagram topologies in ( d , T ) plane, d = D /′ We have also studied the influence of the frequency on the phase boundaries as well as the dynamic tricritical point and found that the topologies of the phase diagrams slightly change. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)