Reentrant behaviour in a highly anisotropic system

Abstract

Abstract The critical behaviour of a spin-1 system made up of weakly coupled chains is analyzed by the linear chain approximation, which first uses the transfer matrix method to find the exact solution of the linear chain and then the Bogolubov variational principle to determine the free energy of the overall system. The model Hamiltonian is a BEG-like with dipolar and quadrupolar couplings and a single-ion anisotropy term. The system is investigated for several ratios of interchain and intrachain interaction terms. A detailed analysis of the role of the interchain terms in the reentrant phenomenon is performed.