(1) 平均场近似(Mean-Field Approximation) 平均场近似基于以下思想:对spin间交互作用简化, 令所有格点对间具有相同的交互作用 J , 并于使用平均场 m 以及关于格点 i的扰动项 δσi 对格点 i 所关联的参数σi使用σi=⟨σi⟩−δσi=m−δσi进行表现。 基于该表现,并于忽略二次扰动项(例如 δ...
而对于平均场近似(Mean Field Approximation,简称MFA)所得的磁化强度可以表达为: ,(1-33) 其中q是最近邻自旋的数目,对于二维正方晶格来说q=4。 图1.5严格解与平均场近似所得二维Ising模型磁化强度的比较。 在图1.5中,与平均场近似所得的解(TC=4K)相比,严格解(TC=2.269K)有着更低的临界温度TC,而且磁化强度...
lattice is calculated using the recently proposed transfer-matrix version of a mean-field approximation. For two-layered case, the present results (Tc/J = 3.20755(5) and 3.62279(2) for the open and periodic boundary conditions, respectively) improve considerably on the previous estimation obtained...
and Saad, D.: Generalized mean field approximation for parallel dynamics of the Ising model. Journal of Statistical Mechanics: Theory and Experiment 2014, P07001 (2014)Hamed Mahmoudi and David Saad. Generalized mean field approximation for parallel dynamics of the ising model. Journal of ...
11、而对于平均场近似(Mean Field Approximation,简称MFA)所得的磁化强度可以表达为:,(1-33)其中q是最近邻自旋的数目,对于二维正方晶格来说q=4。图1.5 严格解与平均场近似所得二维Ising模型磁化强度的比较。在图1.5中,与平均场近似所得的解(TC=4K)相比,严格解(TC=2.269K)有着更低的临界温度TC,而且磁化强度...
The Ising model in the presence of a random field is investigated within the mean field approximation based on Landau expansion. The random field is drawn from the asymmetric and anisotropic bimodal probability distribution P ( h i ) = p δ ( h i h 0 ) + q δ ( h i + λ h 0 )...
Gulpinar investigated the critical behavior of ultrasound wave absorption coefficient in the metamagnetic Ising model within the mean-field approximation [38]. Acoustic Signatures of the Phases and Phase Transitions in the Blume Capel Model with Random Crystal Field Here we use a quantum simulator comp...
而对于平均场近似(Mean Field Approximation ,简称MFA)所得的磁 化强度可以表达为: ()T k h qJM M N h T M B B B μμ+==11tanh ,, (1-33) 其中q 是最近邻自旋的数目,对于二维正方晶格来说q =4。 图 严格解不平均场近似所得二维Isi ng 模型磁化强度的比较。
First, we introduce the kinetic Ising model and its statistical properties of interest. Second, we introduce our framework for the Plefka approximation methods from a geometric perspective. To explain how it works, we derive the classical naive and TAP mean-field approximations under the proposed ...
molecular dynamics simulationstemperature dependenceThe kinetic Ising model in the mean field approximation is applied to study the equilibrium and kinetic ... KK Liang,M Hayashi,YJ Shiu,... - 《Physical Chemistry Chemical Physics》 被引量: 26发表: 2003年 Thermodynamic Limit for the Ising Model ...