Band-gap engineering by Bi intercalation of graphene on Ir(111)
Band-gap engineering by Bi intercalation of graphene on Ir(111)
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Ir(111) 上石墨烯 Bi 插层的带隙工程
DOI：
10.1103/physrevb.93.165437
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发表时间：
2016
影响因子：
3.7
通讯作者：
A. A. Khajetoorians
中科院分区：
文献类型：
--
作者：
J. Warmuth;A. Bruix;M. Michiardi;T. Hänke;M. Bianchi;J. Wiebe;R. Wiesendanger;B. Hammer;P. Hofmann;A. A. Khajetoorians
我们报道了在Ir(111)单晶上生长的石墨烯下面的单层铋的结构和电子性质。扫描隧道显微镜(STM)显示了铋嵌入后的六方表面结构和位错网络，我们将其归因于Ir(111)表面上的ABI结构。从头算结果表明，这种铋结构是最有利的能量结构，说明扫描隧道显微镜测量结果对插入铋原子附近的C原子最敏感。此外，在角分辨光电子能谱中，铋的插层在石墨烯的狄拉克点处引起了带隙(EV)和全面掺杂。我们将带隙的出现归因于石墨烯/Ir(111)界面沿Moiré结构的某些部分有利地形成的位错网络。
We report on the structural and electronic properties of a single bismuth layer intercalated underneath a graphene layer grown on an Ir(111) single crystal. Scanning tunneling microscopy (STM) reveals a hexagonal surface structure and a dislocation network upon Bi intercalation, which we attribute to aBi structure on the underlying Ir(111) surface.Ab initiocalculations show that this Bi structure is the most energetically favorable and illustrate that STM measurements are most sensitive to C atoms in close proximity to intercalated Bi atoms. Additionally, Bi intercalation induces a band gap (eV) at the Dirac point of graphene and an overalldopingas seen in angular-resolved photoemission spectroscopy. We attribute the emergence of the band gap to the dislocation network which forms favorably along certain parts of the moiré structure induced by the graphene/Ir(111) interface.