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采用MonteCarlo方法对离散混合经典Heisenberg自旋体系在周期性外场驱动下动态相变行为进行了模拟计算 .在典型Heisenberg自旋体系的哈密顿量基础上 ,引入表征非晶相的随机各向异性能项 (比例为X )和表征晶体相的单轴各向异性能项 (比例为 1-X) ,考察了该混合自旋体系磁滞后回线面积Aarea 随X和单轴各向异性常数A及随机各向异性常数D的变化规律 ,并确定了该类自旋体系动态相变新的滞后标度关系Aarea-AδDηXσ,主要计算结论 :1)在某个Xmin 值 ,磁滞回线面积取得极小值 ;2 )上述滞后标度指数δ ,η ,σ为常数 ,其中δ +η=0 .9,与二类纯自旋体系的相应值相同 ;3)Xmin 随log(A D)值变化 ,有很好的 S型关系 .混合Heisenberg自旋体系的动态相变理论模型对于目前得到广泛重视的非晶 纳米晶双相体系磁性材料应用研究有一定的理论指导意义 .
The Monte Carlo method was used to simulate the dynamic behavior of the discrete mixed classical Heisenberg spin system driven by periodic external field. Based on the Hamiltonian of the typical Heisenberg spin system, the random anisotropic energy (Ratio is X) and uniaxial anisotropy energy (ratio is 1-X) characterizing the crystal phase, the relationship between the hysteresis loop area Aarea and the uniaxial anisotropy A and The random variation of anisotropy constant D, and the new lagging scale relation Aarea-AδDηXσ of the dynamic phase transition of the spin system has been determined. The main conclusions are as follows: 1) At a certain value of Xmin, 2) The hysteresis scale index δ, η and σ are constants, where δ + η = 0. 9, which is the same as that of the pure spin system of the second kind. 3) Xmin changes with the log Has a good S-type relationship.The dynamic phase transition theory model of the mixed Heisenberg spin system has certain theoretical significance for the application of the magnetic material of the amorphous nanocrystalline Biphasic system, which is widely valued at present.