Atomic and electronic structures of layered structures formed on the Si(111) and SiC(0001) surfaces: a first-principles study
| Autor: | Chia-Hsiu Hsu, 許嘉修 |
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| Rok vydání: | 2013 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 101 Atomic and electronic structures of metal overlayers on the Si(111) surface were studied by first-principles calculations. For the one-dimensional metal atomic wires on Si(111), we first revisited and examined the models with a honeycomb chain feature for the Au/Si(111)-(5×2) surface reconstruction systematically. Our newly identified model reproduces certain key features in the angle-resolved photoemission spectroscopy (ARPES) measurement and experimental scanning tunneling microscope (STM) images. Next, similarly structural models for the Ag/Si(111)-c(12×2) phase were also identified from a systematic search. The mechanisms of phase transitions from 3×1 to 6×1 and from 6×1 to c(12×2) have also been examined. The simulated STM images of this c(12×2) model is in excellent agreement with the experimental STM images. On the other hand, for two dimensional metal overlayers grown on Si(111), the band structures of Pb/Si(111)-√7×√3 surface reconstruction were analyzed in detail, and are in good agreement with the identified bands in the experimental study. Finally, we discuss the 2×2 graphene on SiC(0001)-√3×√3. It becomes a buffer layer when graphene growth on SiC(0001) suface, and the Dirac point of graphene will disappear. However, by intercalating Bi or Sb layer to become a buffer layer make the Dirac cone of graphene will preserved. On the other hand, for the Bi and Sb buffer layer the π and π* bands of the graphene exhibit spin–orbit (SO) splitting will be shown. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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