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Updated: Jan 21, 2026
10:23
Synthesis and Functionalization of 3D Nano-graphene Materials: Graphene Aerogels and Graphene Macro Assemblies
Published on: November 5, 2015
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Strong magnetophonon oscillations in extra-large graphene
P Kumaravadivel1,2, M T Greenaway3,4, D Perello1,2
1School of Physics & Astronomy, University of Manchester, Manchester, M13 9PL, UK.
Nature Communications
|July 28, 2019
Summary
Wider van der Waals devices reveal new quantum effects. Wider graphene/hexagonal boron-nitride Hall bars show resonant scattering, enabling precise study of electron-phonon interactions.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Transport
Background:
- Van der Waals materials and heterostructures are key for quantum transport studies.
- Current experiments are limited by small device dimensions (micrometre scale).
Purpose of the Study:
- Investigate quantum transport phenomena in wider van der Waals devices.
- Explore the impact of device width on observed quantum effects.
- Develop a spectroscopic method for electron-phonon interaction studies.
Main Methods:
- Fabrication of graphene/hexagonal boron-nitride Hall bar devices.
- Magnetotransport measurements on devices with varying lateral dimensions.
- Analysis of magnetoresistance oscillations and resonant scattering phenomena.
Main Results:
- Wider devices (>10 micrometres) exhibit distinct magnetoresistance oscillations.
- Oscillations are attributed to resonant scattering of Landau-quantised Dirac electrons by acoustic phonons.
- Accurate determination of graphene's low-energy phonon dispersion curves, identifying transverse acoustic modes as primary scatterers.
Conclusions:
- Device width is critical for observing quantum effects in van der Waals heterostructures.
- Resonant scattering in wider devices provides a precise spectroscopic method for electron-phonon interaction studies.
- This work advances the understanding of quantum phenomena and electron-phonon coupling in 2D materials.
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