First principles study of the Be-C co-doped MgB_2 system

We study the Be-C doped MgB2 system by the first principles method based on density functional theory. The compensation effect between electron type doping and hole type doping is shown in the total density of states on the Fermi level, the real part of optical conductivity, and the number of effective carriers. The compensation mechanisms are discussed. The critical temperatures for different systems are calculated.     

C掺杂ZnO电子结构的第一性原理研究

采用基于密度泛函理论的第一性原理方法,计算了C掺杂纤锌矿ZnO的电子结构。结果表明,C代Zn位属于n型掺杂,且可使系统由直接带隙半导体变为间接带隙半导体;C代O位可产生受主能级,使系统实现p型转变;两种情况共存时,C代Zn位对C代O位有补偿作用,对系统的p型转变不利。     

Be-C共掺MgB2系统的第一性原理研究

用第一性原理方法研究了Be-C共掺MgB2 系统。讨论了电子型掺杂和空穴性掺杂共存对系统的态密度,光电导的实部,有效载流子数的影响。相应的讨论了补偿效应。并计算了超导转变温度