论文标题
通过使用工作函数差异来控制PB沉积石墨烯的狄拉克带状态
Controlling of the Dirac band states of Pb-deposited graphene by using work function difference
论文作者
论文摘要
我们已经在SIC（0001）底物上的PB沉积双层石墨烯（BLG）中进行了扫描隧道显微镜（STM）和角度分辨光发射光谱（ARPE），以研究电子结构对PB沉积量的依赖性。我们已经观察到，PB原子由STM形成岛，而BLG的$π$带则通过ARPES向Fermi级别转移。随着PB的量增加，这种类似孔掺杂的能量转移会增强，我们能够通过4 mL沉积将狄拉克间隙调整到费米水平。考虑到频带分散，我们建议类似孔掺杂的效应与PB岛和BLG/SIC的工作函数之间的差异有关。 BLG/SIC的功能低于Pb。我们的结果提出了一种简单的石墨烯带调节方法，并同时选择了底物和沉积材料。
We have performed scanning tunneling microscope (STM) and angle-resolved photoemission spectroscopy (ARPES) in Pb-deposited bilayer Graphene (BLG) on SiC(0001) substrate to investigate the dependence of the electronic structures on Pb-deposition amount. We have observed that the Pb atoms form islands by STM and the $π$ bands of the BLG shift toward the Fermi level by ARPES. This hole-doping-like energy shift is enhanced as the amount of Pb is increased, and we were able to tune the Dirac gap to the Fermi level by 4 ML deposition. Considering the band dispersion, we suggest that hole-doping-like effect is related to the difference between the work functions of Pb islands and BLG/SiC; the work function of BLG/SiC is lower than that of Pb. Our results propose an easy way of band tuning for graphene with appropriate selection of both the substrate and deposited material.
