论文标题
石墨烯，硅和德国烯中等离子体激发的第一原则计算
First-principle calculations of plasmon excitations in graphene,silicene and germanene
论文作者
论文摘要
在随机相近似（RPA）中，使用线性响应时间依赖性密度功能理论研究石墨烯，硅和德国烯中的等离子体激发。在这里，我们研究了这三种材料的等离子体分散行为和外在和内在等离子的寿命。对于外部等离子，我们发现它们的性质与Landau阻尼密切相关。在没有单粒子激发（SPE）的区域中，等离子体色散显示\ sqrt {q}行为，生命周期在RPA水平上是无限的，而在单粒子激发区域中，等离子体分散剂显示出识别性行为，而寿命是有限的。此外，对于固有的等离子，与石墨烯不同，硅和德国烯的等离子体色散行为表现出两峰结构，这可以归因于这两种材料的复杂和杂交带结构。
Plasmon excitations in graphene, silicene and germanene are studied using linear-response time dependent density functional theory within the random phase approximation (RPA). Here, we examine both the plasmon dispersion behavior and lifetime of extrinsic and intrinsic plasmons for these three materials. For extrinsic plasmons, we found that their properties are closely related to Landau damping. In the region without single-particle excitation (SPE), the plasmon dispersion shows a \sqrt{q} behavior and the lifetime is infinite at the RPA level, while in the single-particle excitation region, the plasmon dispersion shows a quasilinear behavior and the lifetime is finite. Moreover, for intrinsic plasmons, unlike graphene, the plasmon dispersion behavior of silicene and germanene exhibits a two-peak structure, which can be attributed to the complex and hybridized band structure of these two materials.
