AI 中文总结
该研究解释了SiC上外延石墨烯的金插层产生的驻波和M点附近QPI特征，通过T矩阵处理的环形散射体模型，其结果与FT-STS测量及实空间驻波、局域态密度对比度的实验观察一致。
AI 中文摘要
在SiC上的外延石墨烯下方进行金插层会产生一种团簇相，其具有异常的驻波和集中在石墨烯M点附近的准粒子干涉（QPI）特征。我们表明，这可以通过金插层在石墨烯空心位下方来解释，该插层会在周围六个碳原子上诱导出局域散射势。在T矩阵处理框架内，这种环形散射体产生以M点为中心的椭圆形QPI结构，与实验傅里叶变换扫描隧道谱（FT-STS）测量结果一致。我们进一步表明，这些QPI特征自然产生了在实空间中观察到的近定态驻波图案。最后，我们计算了小金团簇上和团簇外的局域态密度对比度，表明其符号和大小强烈依赖于能量，与实验观察结果相符。
英文摘要
Gold intercalation beneath epitaxial graphene on SiC produces a cluster phase with unusual standing waves and quasiparticle-interference (QPI) features concentrated near the graphene M points. We show that this can be explained by Au intercalation below graphene hollow sites, which induces a local scattering potential on the six surrounding carbon atoms. Within a T-matrix treatment, this ring-like scatterer produces elliptical QPI structures centered near M, in agreement with the experimental FT-STS measurements. We further show that these QPI features naturally generate the nearly stationary standing-wave patterns observed in real space. Finally, we compute the local-density-of-states contrast on and off a small cluster and show that its sign and magnitude are strongly energy dependent, consistent with the experimental observations.
Comments9 pages, 6 figures
