Resumen de Critical and compensation temperatures for the mixed spin-3/2 and spin-5/2 Ising model95

Nicolás de la Espriella Vélez, C. Ortega López, F. Torres Hoyos

• We have studied the critical and compensation temperatures of a ferrimagnetic Ising system with mixed spins S^A_i=+-3/2, +-1/2 and "sigma"^B_j = +-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^A_i <-->"sigma"^B_j) and next nearest neighbord interactions between spins of the same type (S^A_i<-->S^A_j). We investigate the effects of crystal field D and the J_2 ferromagnetic coupling of spins S^A_i on the critical and compensation temperatures of the system, calculating the phase diagrams at finite temperature at the (D/|J_1|,k_BT/|J_1) and (J_2/|J_1|k_BT/|J_1) planes. When the Hamiltonian includes antiferromagnetic coupling between spins S^A_i and "sigma"^B_j, ferromagnetic between spins S^A_i 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^A_i.