对具有蜂窝点阵结构的S=2横向Ising模型基态磁性质的研究  

Ground-state magnetic properties of the spin-2 transverse Ising model with the crystal field in honeycomb lattice

作　　者：赵杰[1] 许星光[1] 魏国柱[2] 

机构地区：[1]辽宁石油化工大学理学院,辽宁抚顺113001 [2]东北大学理学院,辽宁沈阳110006

出　　处：《武汉科技大学学报》2008年第2期193-197,共5页Journal of Wuhan University of Science and Technology

基　　金：教育部博士点基金资助项目(20040145019)

摘　　要：对具有蜂窝点阵结构的S=2横向Ising模型,采用相关有效场理论,推导出系统的有限温度及基态纵向和横向磁矩公式,采用数值计算方法得到了基态的磁化曲线,重点考察了横场对系统基态磁性质的影响。研究表明,系统基态磁矩随晶场或横场的变化发生了三种相变:一级有序-有序相变,一级有序-无序相变,二级有序-无序相变。得到了横向磁场会减弱系统发生一级相变趋势的结论。The spin-2 transverse Ising model with the crystal field in honeycomb lattice is investigated by using the correlated effective field theory. The expressions of transverse and longitudinal magnetization at the finite temperature and the ground state are obtained. With numerical calculation the ground-state magnetization curves are arrived at. The influences of the transverse field on the groundstate magnetic properties of the system are discussed as a focus. It is found that there are three phase transitions in the ground state of the system with the change of the crystal field and the transverse field： the first order-order phase transitions, the first order-disorder phase transitions, and the second order-disorder phase transitions. It is thus concluded that the transverse field can weaken the first order phase transition trend of the system.

关 键 词：相关有效场理论 基态 磁化曲线 一级相变 

分 类 号：O482.52[理学—固体物理]