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Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Atomic hole doping of graphene.
Isabella Gierz1, Christian Riedl, Ulrich Starke
1Max-Planck-Institut für Festkörperforschung, D-70569 Stuttgart, Germany.
Nano Letters
|December 5, 2008
Summary
Controlling charge carriers in graphene is key for nanoscale electronics. Adsorbing bismuth, antimony, or gold atoms effectively dopes graphene, enabling new possibilities for large-scale production.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Graphene's unique electronic properties are crucial for advanced nanoscale electronic devices.
- Precise control over charge carrier density and type is essential for tailoring graphene's performance.
- Epitaxial graphene monolayers offer a promising platform for electronic applications.
Purpose of the Study:
- To investigate methods for achieving substantial hole doping in epitaxial graphene monolayers.
- To explore the effect of adsorbing specific elements (bismuth, antimony, gold) on graphene's electronic band structure.
- To assess the potential of atomic doping for scalable graphene production.
Main Methods:
- Angle-resolved photoemission spectroscopy (ARPES) was employed to analyze the electronic band structure.
- Epitaxial graphene monolayers were synthesized and subjected to adsorption of bismuth, antimony, and gold.
- Changes in the Dirac point and carrier concentration were measured using ARPES.
Main Results:
- Adsorption of bismuth, antimony, and gold successfully induced substantial hole doping in epitaxial graphene.
- The conical band structure of graphene was significantly modified by the adsorbed atoms.
- Gold adsorption shifted the Dirac point into unoccupied electronic states.
- Atomic doping demonstrated feasibility for large-scale graphene production.
Conclusions:
- Atomic adsorption is a viable and effective strategy for controlling charge carriers in graphene.
- This doping method offers a pathway towards tunable electronic properties in graphene-based devices.
- The scalability of atomic doping presents significant opportunities for industrial applications of graphene.
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