Two-dimensional electron and hole gases at the surface of graphite

作者：С. В. Морозов, Kostya S. Novoselov, Fred Schedin, Da Jiang, А. А. Firsov, Andre K. Geim · 发表于：Physical Review B · 年份：2005 · DOI：10.1103/physrevb.72.201401 · 被引用次数：185 · 研究领域：Graphene research and applications、Quantum and electron transport phenomena、Topological Materials and Phenomena

We report two-dimensional (2D) electron and hole gases induced at the surface of graphite by the electric field effect. The 2D gases reside within a few near-surface atomic layers and exhibit mobilities up to 15 000 and $60\phantom{\rule{0.2em}{0ex}}000\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{2}∕\mathrm{V}\phantom{\rule{0.2em}{0ex}}\mathrm{s}$ at room and liquid-helium temperatures, respectively. The mobilities imply ballistic transport on $\ensuremath{\mu}\mathrm{m}$ scale. Pronounced Shubnikov--de Haas oscillations reveal the existence of two types of charge carries in both electron and hole gases.