Department of Physics, Universidad Simón Bolívar, Caracas 1080, Venezuela.
J Phys Condens Matter. 2011 May 4;23(17):176003. doi: 10.1088/0953-8984/23/17/176003. Epub 2011 Apr 14.
We perform Monte Carlo simulations in order to study the magnetic properties of the mixed spin-S = ± 3/2, ± 1/2 and spin-σ = ± 5/2, ± 3/2, ± 1/2 Ising model. The spins are alternated on a square lattice such that S and σ are nearest neighbors. We found that when the Hamiltonian includes antiferromagnetic interactions between the S and σ spins, ferromagnetic interactions between the spins S, and a crystal field, the system presents compensation temperatures in a certain range of the parameters. The compensation temperatures are temperatures below the critical point where the total magnetization is zero, and they have important technological applications. We calculate the finite-temperature phase diagrams of the system. We found that the existence of compensation temperatures depends on the strength of the ferromagnetic interaction between the S spins.
我们进行了蒙特卡罗模拟，以研究混合自旋 S = ± 3/2、± 1/2 和自旋 σ = ± 5/2、± 3/2、± 1/2 的 Ising 模型的磁性质。自旋在正方形晶格上交替排列，使得 S 和 σ 是最近邻。我们发现，当哈密顿量包括 S 和 σ 自旋之间的反铁磁相互作用、自旋 S 之间的铁磁相互作用和晶体场时，系统在参数的一定范围内呈现补偿温度。补偿温度是低于临界点的温度，在临界点处总磁化强度为零，它们具有重要的技术应用。我们计算了系统的有限温度相图。我们发现补偿温度的存在取决于 S 自旋之间铁磁相互作用的强度。
