Thermodynamic Properties of Random Transverse Field Mixed Spin System in the Presence of Single-Ion Anisotropy  

作　　者：ZHANGYa-Nan YANShi-Lei 

机构地区：[1]DepartmentofPhysics,SuzhouUniversity,Suzhou215006,China [2]ProvincialLaboratoryofThinFilmMaterials,SuzhouUniversity,Suzhou215006,China

出　　处：《Communications in Theoretical Physics》2003年第3X期375-380,共6页理论物理通讯（英文版）

摘　　要：We study the thermodynamic properties of random transverse field mixed spin system in the presence of single-ion anisotropy on a square lattice. By making use of the effective field theory and a cutting approximation, the detailed phase diagrams are described and some interesting results are found under trimodal random transverse field distribution. A small single-ion anisotropy can magnify magnetic ordering region at low temperatures and existence of a large transverse field can assist the occurrence of reentrant phenomena. With increasing disorder, second-order phase transitions are shown to change into first-order phase transitions. The trajectory of the tricritical point in the phase space as a function of disorder is presented. These indicate a strong correlation with the corresponding to trimodal transverse field distribution.

关 键 词：热力学性质 混合自旋系统 单离子各向异性 随机横向领域 量子通道 量子论 

分 类 号：O413[理学—理论物理] O414.1[理学—物理]