Two-dimensional electron and hole gases at the surface of graphite
نویسندگان
چکیده
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 60 000 cm2/V s at room and liquid-helium temperatures, respectively. The mobilities imply ballistic transport on m scale. Pronounced Shubnikov–de Haas oscillations reveal the existence of two types of charge carries in both electron and hole gases.
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