零温下二维绝缘铁磁体的磁振子软化  

Magnon Softening in Two-Dimensional Insulating Ferromagnet Under Zero Absolute Temperature

作　　者：成泰民[1] 鲜于泽[1] 杜安[1] 

机构地区：[1]东北大学理学院,辽宁沈阳110004

出　　处：《东北大学学报（自然科学版）》2005年第6期609-612,共4页Journal of Northeastern University(Natural Science)

基　　金：国家自然科学基金资助项目(60031001)

摘　　要：在二维正方绝缘铁磁系统基础上建立了一个磁振子-声子相互作用模型·利用格林函数方法研究了磁振子-声子相互作用下的二维绝缘铁磁体的磁振子谱,计算了布里渊区的主要对称点线上的磁振子色散曲线·发现在布里渊区边界区域磁振子谱的软化和磁振子谱线增宽最明显·比较了纵向声子与横向声子对磁振子谱的软化与磁振子谱线增宽的影响,也讨论了各项参数的变化对磁振子谱的软化与磁振子谱线增宽的影响·A magnon-phonon interaction model is developed in two-dimensional insulating ferromagnet of which the magonon spectrum is studied in accordance to Matsubara-Green function. The magnon dispersion curve is calculated on the main symmetric points lines in Brillouin zone for different parameters in the system. It is found that at the boundary of the zone the magnon linewidth broadens and magnon softens both most obviously. The influences of longitudinal phonon and transverse phonon on magnon softening and magnon linewidth broadening are compared, and the influences of different parameters on them are also illustrated.

关 键 词：磁振子-声子相互作用 磁振子软化 铁磁体 磁振子谱线增宽 磁振子谱 

分 类 号：O482.523[理学—固体物理] O482.5[理学—物理]