计及所有长程库仑作用一维双原子链晶格振动的色散关系  

Dispersion relation of one-dimensional diatomic chain Lattice vibration with long-range Coulomb interactions

作　　者：陈志远[1] 戴国田[2] 谢菊芳[3] 张端明[4] 

机构地区：[1]咸宁学院电子与信息工程学院,湖北咸宁437100 [2]湖北大学材料科学与工程学院,湖北武汉430062 [3]湖北大学物理学与电子技术学院,湖北武汉430062 [4]华中科技大学物理学院,湖北武汉430074

出　　处：《湖北大学学报（自然科学版）》2010年第3期279-282,286,共5页Journal of Hubei University：Natural Science

基　　金：国家自然科学基金(50872038)资助;咸宁学院重点基金项目(KY09041)资助

摘　　要：在简谐近似和周期性边界条件下,推导考虑所有原子长程库仑作用一维双原子链晶格振动的色散关系.分析讨论长程库仑作用对色散关系的影响,结果表明:随着长程库仑作用的增强,晶格振动模的频率不断减小、色散关系的频隙逐渐变窄直到消失,并且光学支渐渐深陷入声学支中,最终导致光学支在布里渊区中心的最高频率挪到极低频处.Under the harmonic approximation of lattice vibration and the periodic boundary condition,the general expression of the dispersion relation of one-dimensional diatomic chain with long-range Coulomb interactions was obtained.The effect of long-range Coulomb interactions on the dispersion relation was analyzed and discussed.The results showed that,with the enhancement of long-range Coulomb interaction,the frequency of vibration modes decreased,the frequency gap of the dispersion relations gradually narrowed till disappeared,and the optical branch gradually got into the acoustics branch,further the maximum frequency of optical branch in the Brillouin zone center moved to extremely low frequency.

关 键 词：晶格振动 长程库仑作用 色散关系 

分 类 号：O481[理学—固体物理]