Phase diagram of the ferrimagnetic mixed-spin Blume-Capel model with four-spin and next-nearest neighbor interactions

摘要

Afiniteclusterapproximationbasedonasingleclustertheoryisdevelopedforaferrimagneticmixedspin-1/2andspin-1Blume-Capelmodelwithfour-spininteractionJ4andnext-nearestneighborcouplingsJ'.Thestateequationsarederivedforthetwo-dimensionalsquarelatticeandthephasediagramisexplored.WefoundthatthesystemcanexhibitsbothcriticalandtricriticalbehavioraccordingtoappropriatevaluesofJ',DandJ4...