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Resistance noise in electrically biased bilayer graphene
Atindra Nath Pal1, Arindam Ghosh
1Department of Physics, Indian Institute of Science, Bangalore 560 012, India. atin@physics.iisc.ernet.in
Physical Review Letters
|April 28, 2009
Summary
Low-frequency resistance noise in bilayer graphene is linked to its band structure, showing a minimum at zero band gap. This finding aids in studying graphene
Area of Science:
- Condensed matter physics
- Materials science
Background:
- Bilayer graphene exhibits unique electronic properties influenced by its band structure.
- Understanding charge transport and electronic properties is crucial for graphene-based applications.
Purpose of the Study:
- To investigate the relationship between low-frequency resistance fluctuations (noise) and the band structure of bilayer graphene.
- To explore the potential of independently tuning the band gap and charge neutrality points for studying graphene's electronic properties.
Main Methods:
- Fabrication and characterization of double-gated bilayer graphene devices.
- Independent tuning of the zero gap and charge neutrality points.
- Measurement and analysis of low-frequency resistance noise.
Main Results:
- Resistance noise in bilayer graphene is strongly correlated with its band structure.
- A distinct minimum in resistance noise is observed when the band gap approaches zero.
- Independent control over the band gap and charge neutrality points was achieved.
Conclusions:
- The study establishes a clear link between resistance noise and bilayer graphene's band structure.
- The observed noise minimum at zero band gap provides insights into charge carrier behavior.
- The developed tuning mechanism offers a versatile platform for further investigations into graphene's electronic characteristics.
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