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Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Electron transport in disordered graphene nanoribbons
Melinda Y Han1, Juliana C Brant, Philip Kim
1Department of Physics and Department of Applied Physics, Columbia University, New York, New York 10027, USA.
Physical Review Letters
|April 7, 2010
Summary
We studied graphene nanoribbons (GNRs) and found a transport gap inversely proportional to width. Electron localization in this gap shows temperature-dependent transport behavior.
Area of Science:
- Condensed matter physics
- Materials science
- Nanotechnology
Background:
- Graphene nanoribbons (GNRs) are promising materials for nanoelectronic devices.
- Understanding electron transport properties in GNRs is crucial for device applications.
Purpose of the Study:
- To investigate electron transport in lithographically fabricated GNRs.
- To determine the relationship between GNR width, length, and transport properties.
Main Methods:
- Fabrication of GNRs with varying widths and lengths using lithography.
- Electron transport measurements at different temperatures.
- Analysis of transport gap, electron localization, and charging effects.
Main Results:
- A length-independent transport gap was observed at the charge neutrality point.
- The transport gap size is inversely proportional to the GNR width.
- Electron transport transitions from thermally activated behavior to variable range hopping with decreasing temperature.
- Charging effects significantly contribute to the activation energy.
Conclusions:
- GNR width is a critical parameter determining the transport gap.
- Electron localization and temperature-dependent transport mechanisms are key features in GNRs.
- Geometric capacitance plays a significant role in the energy landscape of GNRs.
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