Phase transitions of the mixed spin-1/2 and spin-SS Ising model on a three-dimensional decorated lattice with a layered structure

Phase transitions of the mixed spin- 1/2 and spin-SS (S≥1/2S≥1/2) Ising model on a three-dimensional (3D) decorated lattice with a layered magnetic structure are investigated within the framework of a precise mapping relationship to the simple spin- 1/2 Ising model on a tetragonal lattice. This mapping correspondence yields for the layered Ising model of mixed spins plausible results either by adopting the conjectured solution for the spin- 1/2 Ising model on the orthorhombic lattice [Z.-D. Zhang, Philos. Mag. 87 (2007) 5309–5419] or by performing extensive Monte Carlo simulations for the corresponding spin- 1/2 Ising model on the tetragonal lattice. It is shown that the critical behaviour markedly depends on a relative strength of axial zero-field splitting parameter, inter- and intra-layer interactions. The striking spontaneous order captured to the ‘quasi-1D’ spin system is found in a restricted region of interaction parameters, where the zero-field splitting parameter forces all integer-valued decorating spins towards their ‘non-magnetic’ spin state.