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Updated: Jun 25, 2026
11:42
Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Energy gaps in etched graphene nanoribbons.
C Stampfer1, J Güttinger, S Hellmüller
1Solid State Physics Laboratory, ETH Zurich, 8093 Zurich, Switzerland.
Physical Review Letters
|March 5, 2009
Summary
Researchers studied graphene nanoribbons and identified two key voltage scales. These scales explain suppressed conductance by revealing the charging energy of localized states and the disorder potential strength.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Graphene nanoribbons exhibit complex electronic transport properties.
- Understanding conductance suppression in these nanostructures is crucial for device applications.
Purpose of the Study:
- To experimentally characterize the voltage scales governing suppressed conductance in etched graphene nanoribbons.
- To differentiate the contributions of localized states and disorder potential to conductance suppression.
Main Methods:
- Transport measurements on etched graphene nanoribbons.
- Utilizing gate voltage variations to probe electronic states.
- Employing a single-electron transistor to verify electron addition to localized states.
Main Results:
- Two distinct voltage scales were experimentally extracted.
- One scale relates to the charging energy of localized states (approx. 10 meV).
- The other scale relates to the disorder potential strength (approx. 100 meV).
- Gate lever arm variations indicate spatial distribution of localized states.
Conclusions:
- The study provides experimental evidence for distinct energy scales in graphene nanoribbons.
- These scales are critical for understanding and controlling electron transport.
- Findings contribute to the fundamental understanding of disordered quantum systems.
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