Second order resonant Raman scattering in single layer tungsten disulfide (WS${}_2$)

Abstract

Resonant Raman spectra of single layer WS${}_2$ flakes are presented. A second order Raman peak (2LA) appears under resonant excitation with a separation from the E${}_{2g}^1$ mode of only $4$cm${}^{-1}$. Depending on the intensity ratio and the respective line widths of these two peaks, any analysis which neglects the presence of the 2LA mode can lead to an inaccurate estimation of the position of the E${}_{2g}^1$ mode, leading to a potentially incorrect assignment for the number of layers. Our results show that the intensity of the 2LA mode strongly depends on the angle between the linear polarization of the excitation and detection, a parameter which is neglected in many Raman studies.

6 pages, 4 figures

References in corpus (3)

• The Raman Fingerprint of Graphene
• Anomalous Lattice Vibrations of Single and Few-Layer MoS2
• Optical signature of symmetry variations and spin-valley coupling in atomically thin tungsten dichalcogenides

Cited by in corpus (5)

• Helicity resolved Raman scattering of MoS2, MoSe2, WS2 and WSe2 atomic layers
• Splitting of the monolayer out-of-plane A'1 Raman mode in few-layer WS2
• Electron-phonon and phonon-phonon anharmonic interactions in 2H-MoX2 (X=S, Te): A comprehensive Resonant Raman study
• Revealing the nature of excitons in liquid exfoliated monolayer WS2
• Raman Scattering with infrared excitation resonant with MoSe${}_2$ indirect band gap