零温下一维绝缘铁磁链的磁振子软化

Softening of Magnon of One Dimensional Insulating Ferromagnetic Chain at Absolute Zero Temperature

在一维绝缘铁磁链系统基础上建立一个磁振子-声子相互作用模型.利用格林函数方法研究磁振子-声子相互作用下的一维绝缘铁磁链的磁振子谱,计算布里渊区的磁振子色散曲线.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.讨论各项参数的变化对磁振子谱的软化与对磁振子谱线增宽的影响.

A magnon-phonon interaction model is built in one dimensional insulating ferromagnetic chain. By using Matsubara Green function theory, we have studied the magonon spectrum, and calculated the magnon dispersion curve on the Brillouin zone for different parameters in the system. It is conclud ed that at the boundary of Brillouin zone there is a strong broadening on the magnon linewidth and softening, and the influences of the parameters are also illustrated.