Revealing Anisotropic In-plane Raman Scattering by Polarization-resolved Analysis in MoS2

Teng-De Huang^1*, Kristan Bryan Simbulan¹, Yu-Fan Chiang¹, Yann-Wen Lan¹, Ting-Hua Lu¹

¹Physics, National Taiwan Normal University, Taipei, Taiwan

* Presenter:Teng-De Huang, email:tengte610165@livemail.tw

The effect of peculiar in-plane lattice vibration in monolayer, bilayer, and bulk molybdenum disulfide are oftentimes ignored when analyzing the material’s lattice behaviors. However, in this latest work, we observed variations in the relative intensity of the two most dominant peaks of the Raman spectrum of MoS2 via polarized micro-Raman spectroscopy using elliptically polarized incident light. The use of elliptically polarized light has simultaneously provided properties of both the circular and linear polarization of light to the incident Raman polarization vector. This gives an additional degree of freedom affecting the relationship of the lattice vibrations along the in-plane x (E_2gx^1) and y-direction (E_2gy^1). Different ratios of the magnitudes for the E_2gx^1 and E_2gy^1 in the lattice vibrations can be induced by changing the polarization state of the incident light. This work investigates the material’s unexplored fundamental phonon property which may enlighten past and future studies involving phonon behaviors.

Keywords: polarizations, phonons, light-matter interaction, transition metal dichalcogenides, Raman spectroscopy