Resumo

ESPRIELLA VELEZ, N. De La; ORTEGA LOPEZ, C.  e  TORRES HOYOS, F.. Critical and compensation temperatures for the mixed spin-3/2 and spin-5/2 Ising model. Rev. mex. fis. [online]. 2013, vol.59, n.2, pp.95-101. ISSN 0035-001X.

We have studied the critical and compensation temperatures of a ferrimagnetic Ising system with mixed spins S_i^A= ±3/2, ±1/2 and σ_j^B = ±5/2, ±3/2, ±1/2, by using Monte Carlo simulations. The spins are alternated on a square lattice, such that nearest neighbor interactions occur between different spins (S_i^A ↔ σ_j^B) and next nearest neighbors interactions between spins of the same type (S_i^A ↔ S_i^A). We investigate the effects of crystal field D and the J₂ ferromagnetic coupling of spins S_i^A on the critical and compensation temperatures of the system, calculating the phase diagrams at finite temperature at the (D/|J₁| ,k_BT/|J₁|) and (J₂/|J₁|,k_BT/|J₁|) planes. When the Hamiltonian includes antiferromagnetic couplings between spins S_i^A and σ_jB, ferromagnetic between spins S_i^A and the term of single ion anisotropy D, the system presents compensation temperatures in a certain range of parameters, which depend on the intensity of the ferromagnetic interaction of spins S_i^A.

Palavras-chave : Ising system; Monte Carlo; critical temperatures; compensation temperatures; crystal field.

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