Observation of interlayer phonon modes in van der Waals heterostructures

C. H. Lui, Zhipeng Ye, Chao Ji, Kuan Chang Chiu, Cheng Tse Chou, Trond I. Andersen, Casie Means-Shively, Heidi Anderson, Jenn Ming Wu, Tim Kidd, Yi Hsien Lee, Rui He

Research output: Contribution to journalArticle

116 Scopus citations

Abstract

We have investigated the vibrational properties of van der Waals heterostructures of monolayer transition metal dichalcogenides (TMDs), specifically MoS2/WSe2 and MoSe2/MoS2 heterobilayers and twisted MoS2 bilayers, by means of ultralow-frequency Raman spectroscopy. We discovered Raman features (at 30-40cm-1) that arise from the layer-breathing mode (LBM) vibration between the two incommensurate TMD monolayers in these structures. The LBM Raman intensity correlates strongly with the suppression of photoluminescence that arises from interlayer charge transfer. The LBM is generated only in bilayer areas with direct layer-layer contact and an atomically clean interface. Its frequency also evolves systematically with the relative orientation between the two layers. Our research demonstrates that the LBM can serve as a sensitive probe to the interface environment and interlayer interactions in van der Waals materials.

Original languageEnglish
Article number165403
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume91
Issue number16
DOIs
StatePublished - Apr 8 2015

Fingerprint Dive into the research topics of 'Observation of interlayer phonon modes in van der Waals heterostructures'. Together they form a unique fingerprint.

  • Cite this

    Lui, C. H., Ye, Z., Ji, C., Chiu, K. C., Chou, C. T., Andersen, T. I., Means-Shively, C., Anderson, H., Wu, J. M., Kidd, T., Lee, Y. H., & He, R. (2015). Observation of interlayer phonon modes in van der Waals heterostructures. Physical Review B - Condensed Matter and Materials Physics, 91(16), [165403]. https://doi.org/10.1103/PhysRevB.91.165403