BaSe的准粒子能带结构

Abstract

【中文摘要】 运用标准的准粒子GW方法重新考察了BaSe的准粒子能带结构.为便于比较,同时计算了局域密度近似(LDA)和广义梯度近似(GGA)下的能带.结果表明,LDA和GGA方法都不能准确描述这个材料的带隙.与实验测量值对比,其误差分别达到39.9%和32.6%.GW准粒子能带的结果则可以对其带隙作出大幅度的修正,得到与实验测量相当符合的理论结果.与已有的计算结果不同,B1结构BaSe准粒子能带具有Γ点直接带隙特性,表明在Ba价电子组态中考虑4d电子的作用至关重要. 【英文摘要】 The electron structure of barium's VIB compound is not clearly known yet. The main problem is that not only the band gap calculated by using DFT (density functional theory) has a large discrepancy compared with experimental results,but also the theoretical values of band gap are inconsistent for different research groups.In order to resolve these problems, this paper makes the Green function-screened coulomb interaction quasiparticle theory(GW) calculation to get the quasiparticle band structure of BaSe.For...