The ultra-low-frequency shear modes of 2-4 layer graphenes observed in their scroll structures at edges

Abstract

The in-plane shear modes between neighbor-layers of 2-4 layer graphenes (LGs) and the corresponding graphene scrolls rolled up by 2-4LGs were investigated by Raman scattering. In contrast to that just one shear mode was observed in 3-4LGs, all the shear modes of 3-4LGs were observed in 3-4 layer scrolls (LSs), whose frequencies agree well with the theoretical predication by both a force-constant model and a linear chain model. In comparison to the broad width (about 12cm${}^{-1}$) for the G band in graphite, all the shear modes exhibit an intrinsic line width of about 1.0 cm${}^{-1}$. The local electronic structures dependent on the local staking configurations enhance the intensity of the shear modes in corresponding 2-4LSs zones, which makes it possible to observe all the shear modes. It provides a direct evidence that how the band structures of FLGs can be sensitive to local staking configurations. This result can be extended to n layer graphene (n > 4) for the understanding of the basic phonon properties of multi-layer graphenes. This observation of all-scale shear modes can be foreseen in other 2D materials with similar scroll structures.

14 pages, 5 figures

References in corpus (8)

• The Raman Fingerprint of Graphene
• Two Dimensional Atomic Crystals
• The structure of suspended graphene sheets
• Raman Spectroscopy of Graphene Edges
• Phonon Linewidths and Electron Phonon Coupling in Nanotubes
• Reduction of Fermi velocity in folded graphene observed by resonance Raman spectroscopy
• Effect of external conditions on the structure of scrolled graphene edges
• Imaging Stacking Order in Few-Layer Graphene

Cited by in corpus (9)

• Phonon and Raman scattering of two-dimensional transition metal dichalcogenides from monolayer, multilayer to bulk material
• The Interlayer Shear Modes in Twisted Multi-layer Graphenes: Interlayer coupling, Davydov Splitting and Intensity Resonance
• Observation of interlayer phonon modes in van der Waals heterostructures
• Interlayer Interactions in Anisotropic Atomically-thin Rhenium Diselenide
• Coupling and stacking order of ReS2 atomic layers revealed by ultralow-frequency Raman spectroscopy
• Resonant Low Frequency Interlayer Shear Modes in Folded Graphene Layers
• Temperature-activated layer-breathing vibrations in few-layer graphene
• Stacking-dependent shear modes in trilayer graphene
• Scroll configurations of carbon nanoribbons