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Updated: May 22, 2026
11:42
Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Two-dimensional phonon transport in graphene
Denis L Nika1, Alexander A Balandin
1Department of Electrical Engineering, Bourns College of Engineering, University of California, Riverside, CA 92521, USA.
Summary
Phonons, the quanta of crystal lattice vibrations, exhibit unique transport properties in graphene, a quasi-two-dimensional material. This review explores their thermal conductivity, influenced by strain, defects, and isotopes.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Phonons (quanta of crystal lattice vibrations) are crucial in graphene, acting as primary heat carriers (acoustic phonons) and enabling structural analysis (optical phonons).
- Graphene's quasi-two-dimensional nature leads to distinct phonon energy dispersion and scattering rates compared to bulk materials.
- Understanding phonon behavior is key to novel heat conduction phenomena in graphene.
Purpose of the Study:
- To review theoretical approaches for phonon transport in graphene.
- To analyze the contributions of in-plane and cross-plane phonon modes.
- To compare theoretical findings with experimental thermal conductivity data.
Main Methods:
- Theoretical modeling of phonon transport in graphene.
- Analysis of phonon dispersion and scattering rates.
- Comparison of theoretical predictions with experimental thermal conductivity measurements.
Main Results:
- Phonon transport properties in graphene differ significantly from bulk crystals due to its 2D nature.
- In-plane and cross-plane phonon modes play distinct roles in thermal conductivity.
- Strain, defects, and isotopes demonstrably affect phonon transport and thermal conductivity.
Conclusions:
- Graphene's unique 2D structure dictates unusual phonon transport and heat conduction properties.
- Theoretical frameworks provide insights into phonon behavior, validated by experimental data.
- Further research on factors like strain and defects can optimize graphene's thermal management applications.
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