AlB_2型结构WB_2点阵动力学的第一性原理研究  

First- principles Study of Lattice Dynamical of WB_2 within AlB_2- type Structure

作　　者：汪月琴[1] 严少平[1] 

机构地区：[1]安徽理工大学理学院,安徽淮南232001

出　　处：《安徽理工大学学报（自然科学版）》2015年第1期28-30,共3页Journal of Anhui University of Science and Technology:Natural Science

基　　金：安徽理工大学博硕基金资助项目(2012sbxm032)

摘　　要：对Al B2型结构的二硼化物的超导进行了大量研究,试图寻找新的高温超导体。为了研究硬材料WB2的超导电性,利用基于密度泛函理论的第一性原理计算,研究了Al B2型结构WB2的点阵动力学性质,并与高温超导体Mg B2的相关性质作了比较。WB2的能带在费米能级沿Γ-A方向有两条双重简并的能带。带心声子计算结果表明,声子频率全部来源于B原子振动关联模式的贡献。高频率的B1g和E2g两种声学模式的电声耦合作用较强且对超导电性起着决定性的作用。WB2有着与Mg B2类似的高温超导性质。In order to study the superconductivity of hard materials WB2,the first principles calculations based on the density functional theory was used to study the lattice dynamics of Al B2- type structure WB2,which is compared with the related properties of high- temperature superconductor Mg B2. The band structure of WB2 at the fermi energy has two doubly- degenerated bands along the Γ- A direction. The zone- center phonon result showed that all the phonon frequencies are contributed by the motion of B- vibrations- related modes. The electron- phonon coupling（ EPC） of B1 gand E2gphonon modes are strong,which plays a decisive role in superconductivity. The high- temperature superconducting properties of WB2 are similar to Mg B2.

关 键 词：第一性原理 点阵动力学 超导电性 

分 类 号：O511.4[理学—低温物理]