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Updated: Jun 3, 2026
10:36
Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials
Published on: January 21, 2016
Magnetoresistance in single-layer graphene: weak localization and universal conductance fluctuation studies
Yung-Fu Chen1, Myung-Ho Bae, Cesar Chialvo
1Department of Physics and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801-2902, USA.
Summary
We measured magnetoresistance in single-layer graphene at 250 mK. Electron-electron interactions cause phase coherence loss, impacting weak localization and conductance fluctuations.
Area of Science:
- Condensed Matter Physics
- Materials Science
Background:
- Single-layer graphene exhibits unique electronic properties.
- Understanding electron interactions is crucial for graphene's applications.
Purpose of the Study:
- Investigate phase coherence in single-layer graphene.
- Determine the role of electron-electron interactions in carrier scattering.
Main Methods:
- Measurements of magnetoresistance in single-layer graphene.
- Analysis of weak localization (WL) and universal conductance fluctuations (UCF) signatures.
- Experiments conducted at cryogenic temperatures (250 mK).
Main Results:
- Phase coherence loss is attributed to electron-electron interactions.
- Trigonal warping influences scattering at high carrier densities.
- Intra-valley scattering dominates near the Dirac point.
- UCF amplitude correlates with carrier density, indicating coherence loss.
Conclusions:
- Electron-electron interactions are the primary mechanism for phase coherence loss in graphene.
- Graphene's electronic behavior is sensitive to carrier density and scattering mechanisms.
- Findings provide insights into electron transport in 2D materials.
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