Shear and Layer Breathing Modes in Multilayer MoS2

TL;DR

This paper investigates shear and layer breathing vibrational modes in multilayer MoS2 using Raman scattering, revealing layer-dependent behaviors and providing a model applicable to other layered materials for thickness monitoring.

Contribution

It introduces a polarization and symmetry-based Raman method to identify and analyze shear and breathing modes, with a chain model explaining their layer-dependent properties.

Findings

Layer modes shift with the number of layers.

Different scaling behaviors for odd and even layers.

A chain model accurately describes the observed phenomena.

Abstract

We study by Raman scattering the shear and layer breathing modes in multilayer MoS2. These are identified by polarization measurements and symmetry analysis. Their positions change with the number of layers, with different scaling for odd and even layers. A chain model explains the results, with general applicability to any layered material, and allows one to monitor their thickness.