层状Heisenberg亚铁磁系统的温度补偿行为

Temperature Compensation Behavior of Layered Heisenberg Ferrimagnets

采用双时温度格林函数方法讨论了具有层间耦合的蜂窝状晶格3/2和5/2混自旋亚铁磁Heisenberg系统全温区的磁性行为·讨论了晶体场单离子各向异性和层间耦合效应对系统磁矩、转变温度和补偿温度的影响·给出了子晶格磁矩和总磁矩在不同的晶体场单离子各向异性和层间耦合效应随温度变化曲线,系统的转变温度和补偿温度随晶体场单离子各向异性和层间耦合效应变化的相图·分析表明:系统存在多种磁矩曲线,当晶体场单离子各向异性和层间耦合超过最小值(D1min/J和J1min/J)后才会出现补偿现象,补偿温度随D1/J和J1/J的增大而减小,最后趋于不变·

The method of the double-time temperature Green function is used to study theoretically the magnetic properties of a mixed spin-3/2 and spin-5/2 Heisenberg ferrimagnetic system on a layered honeycomb lattice. Particularly, the effects of single-ion anisotropy and interlayer interaction on magnetization, critical and compensation temperature are investigated. Gives the temperature dependence of the total and sublattice magnetization for several values of single-ion anisotropy and interlayer interaction, as well as the critical and compensation temperature as functions of single-ion anisotropy and interlayer interaction. All these indicate that there are several magnetization curves and there will be a compensation behavior only when the single-ion anisotropy and interlayer interaction exceed a minimum (D_(1min)/J and J_(1min)/J). The compensation temperature decreases with increasing D_1/J and J_1/J and it will remain unchanged as a consequence.