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arXiv · 1405.7343

Stacking-dependent shear modes in trilayer graphene

Chun Hung Lui·Zhipeng Ye·Courtney Keiser·Eduardo B. Barros·Rui He
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Abstract

We observed distinct interlayer shear mode Raman spectra for trilayer graphene with ABA and ABC stacking order. There are two rigid-plane shear-mode phonon branches in trilayer graphene. We found that ABA trilayers exhibit pronounced Raman response from the high-frequency shear branch, without any noticeable response from the low-frequency branch. In contrast, ABC trilayers exhibit no response from the high-frequency shear branch, but significant Raman response from the low-frequency branch. Such complementary behaviors of Raman shear modes can be explained by the distinct symmetry of the two trilayer allotropes. The strong stacking-order dependence was not found in the layer-breathing modes, and thus represents a unique characteristic of the shear modes.

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Chun Hung Lui, Zhipeng Ye, Courtney Keiser, Eduardo B. Barros, Rui He. 2014-05-28. Stacking-dependent shear modes in trilayer graphene. https://doi.org/10.1063/1.4906579

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