Zn掺杂对MgB₂电子结构及超导转变温度的影响

来源期刊：中南大学学报(自然科学版)2006年第5期

论文作者：李燕峰 徐慧 宋招权 夏庆林 程仕平

文章页码：925 - 931

关键词：Zn掺杂;第一性原理;电子结构;超导温度

Key words：Zn doped; the first principle; electronic structure; superconductivity temperature

摘    要：建立Zn掺杂含量不同的6个MgB₂模型Mg_1-xZn_xB₂(x=0, 1/18, 1/16, 1/12, 1/8, 1/6),对模型进行参数优化,分析Zn掺杂对MgB₂几何构型的影响;计算纯MgB₂和x为1/6, 1/8, 1/12时掺杂模型的能带结构和态密度,对得到的结果进行分析和处理,并指出Zn掺杂时MgB₂超导临界转变温度T_c变化的大致规律。根据强耦合BCS理论的Mc-Millan公式,推导第一性原理计算公式,计算Zn掺杂MgB₂的超导临界转变温度T_c。

Abstract: Six models of MgB₂ with different Zn concentrations, i.e., Mg_1-xZn_xB₂(x=0, 1/18,1/16, 1/12, 1/8, 1/6) were build up, the modules’parameters were optimized, and their effects on the geometry structure were compared before and after doping. The band structure and density of states(DOS) of pure and Zn doping MgB2were calculated, the law of superconductive critical transition temperature(T_c) of MgB₂ with Zn doping was gotten. The first principle compute formula was deduced based on the BCS theory and Mc-Millan formula and T_c of the Zn doped MgB₂ were computed.

基金信息：教育部高等学校博士点专项科研基金资助项目