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采用双时格林函数理论讨论了二维反铁磁Heisenberg模型的热力学性质.将自旋算符的关联函数在Tyab-likov近似下进行退耦,得到关联函数的自洽方程,从而研究了相变温度下自旋交错磁化的激发情况,求出了系统的平均能量,并将基态的情况与对应的数值模拟结果进行了比较.
Abstract：The thermodynamic properties of the two dimensional antiferromagnetic Heisenberg model are studied in the framework of two-time Green's function theory.With the Tyablibov approximation,the Green's function is decoupled in terms of the correlation functions of spin operators,from which a set of self-consistent equations of the correlation functions are derived.And then,temperature dependence of the magnetization,average energy of the system,and correlation between the nextest neighbors are obtained.
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基本信息:
中图分类号:O482.5
引用信息:
[1]仲崇贵,赵永林,施建珍.自旋1/2的二维反铁磁Heisenberg模型的格林函数理论[J].南通大学学报(自然科学版),2006(04):9-11.
基金信息:
江苏省高校自然科学基金资助项目(05KJB140108)