ReB_2和WB_2电声耦合的第一性原理研究  

ELECTRON-PHONON CONPLING OF ReB_2 AND WB_2 FROM FIRST-PRINCIPLES CALCULATION

作　　者：汪月琴[1] 严少平[1] 戴振翔[2] 

机构地区：[1]安徽理工大学理学院,安徽淮南232001 [2]安徽大学材料物理学院信息材料与器件重点实验室,安徽合肥230039

出　　处：《低温物理学报》2014年第5期369-373,共5页Low Temperature Physical Letters

基　　金：安徽省自然科学基金批准号:(KJ2011Z113)资助的课题~~

摘　　要：采用基于密度泛函微扰理论的第一性原理方法研究了过渡金属化合物ReB2和WB2的声子和电声耦合作用.结果表明,ReB2和WB2都存在弱的电声耦合,电声耦合常数分别为0.23和0.44.电声耦合作用主要来源于B原子振动声子关联模式的贡献.估算得到ReB2的超导温度大约在0~1.5K,WB2的超导温度在0.8~10.7K（取μ＊=0.15~0时）.研究结果表明ReB2和WB2是一类弱的电声耦合超导体,WB2的超导温度大于ReB2的超导温度.The phonon and electron-phonon coupling of ReB2 and WB2 are invesitigated using the first-principles linear response calculations based on the density functional theory. The results showed that the electron-phonon coupling （EPC） in ReB2 and WB2 are both weak, the EPC constants were 0. 23 and 0. 44, respectively. The B-vibrationrelated phonon modes played the most important role in EPC interaction. The estimated superconducting transition temperature Tc for ReB2 and WB2 are 0-1.5 K and 0. 8-10. 7 K, respectively, using the coulomb pseudopotential μ＊ =0. 15-0. The calculated results showed that ReB2 and WB2 are both weak EPC superconductor, and the superconducting transition temperature Tc for WBz was larger than that of Re2.

关 键 词：ReB2 WB2 第一性原理 电声耦合 超导体 

分 类 号：O511.3[一般工业技术—材料科学与工程]