Department of Physics and Center for Functional Nanoscale Materials, Clark Atlanta University, Atlanta, Georgia 30314, USA.
Nanoscale. 2012 Apr 28;4(9):2962-7. doi: 10.1039/c2nr11991a. Epub 2012 Mar 27.
We have studied the electronic characteristics of multilayer epitaxial graphene under a perpendicularly applied electric bias. Ultraviolet photoemission spectroscopy measurements reveal that there is notable variation of the electronic density-of-states in valence bands near the Fermi level. Evolution of the electronic structure of graphite and rotational-stacked multilayer epitaxial graphene as a function of the applied electric bias is investigated using first-principles density-functional theory including interlayer van der Waals interactions. The experimental and theoretical results demonstrate that the tailoring of electronic band structure correlates with the interlayer coupling tuned by the applied bias. The implications of controllable electronic structure of rotationally fault-stacked epitaxial graphene grown on the C-face of SiC for future device applications are discussed.
我们研究了在垂直电场作用下多层外延石墨烯的电子特性。紫外光电子能谱测量表明，在费米能级附近的价带中，电子态密度有显著的变化。利用第一性原理密度泛函理论（包括层间范德华相互作用）研究了石墨和旋转堆叠多层外延石墨烯的电子结构随外加电场的演化。实验和理论结果表明，电子能带结构的剪裁与通过外加偏压调节的层间耦合相关。讨论了在 SiC 的 C 面上生长的旋转层错外延石墨烯的可控电子结构对未来器件应用的意义。
