Interlayer resonant Raman modes in few-layer MoS2

Scheuschner N, Gillen R, Staiger M, Maultzsch J (2015)


Publication Status: Published

Publication Type: Journal article

Publication year: 2015

Journal

Publisher: AMER PHYSICAL SOC

Book Volume: 91

Journal Issue: 23

DOI: 10.1103/PhysRevB.91.235409

Abstract

We report two first-order Raman modes in the spectra of few-layer MoS2 at 286 and 471 cm(-1) that are only observed at excitation energies above 2.4 eV. We show that these normally not observed modes are interlayer modes related to symmetry-forbidden modes of the single layer. Based on group theory, we provide a general treatment and systematic classification of all phonon modes in few-layer crystals with inversion symmetry and/ or horizontal reflection symmetry. The results can thus be applied to different materials like few-layer graphene, transition-metal dichalcogenides, or BN. Moreover, the few-layer specific Raman modes are strongly resonant with the C optical transition in MoS2. We conclude that the corresponding exciton wave function is extended over all layers of the few-layer MoS2, in contrast to the A and B excitons.

Authors with CRIS profile

Involved external institutions

How to cite

APA:

Scheuschner, N., Gillen, R., Staiger, M., & Maultzsch, J. (2015). Interlayer resonant Raman modes in few-layer MoS2. Physical Review B, 91(23). https://doi.org/10.1103/PhysRevB.91.235409

MLA:

Scheuschner, Nils, et al. "Interlayer resonant Raman modes in few-layer MoS2." Physical Review B 91.23 (2015).

BibTeX: Download