Helicity-resolved Raman scattering of MoS 2 bulk crystal.

Authors :: Yang MM
Wu H
Tan L
Ma Y
Zhao YN
Liu Y
Yang FR
Wu CL
Liu XL
Liang BL
Li XL
Source :: Optics letters [Opt Lett] 2023 Feb 15; Vol. 48 (4), pp. 888-891.
Publication Year :: 2023
Abstract: Helicity-resolved Raman spectroscopy (HRRS) can effectively distinguish the Raman modes of two-dimensional (2D) layered materials by phonon symmetry. In this paper, we systematically investigated the phonon helicity selection of basal and edge planes of MoS <subscript>2</subscript> bulk by HRRS. We find that the symmetry of the crystal structure changes the helicity selection of the E <subscript>1g</subscript> , E <superscript>1</superscript> <subscript>2g</subscript> , and A <subscript>1g</subscript> modes in the edge plane. The theoretical calculation results confirm that the E <superscript>1</superscript> <subscript>2g</subscript> and A <subscript>1g</subscript> modes of the basal plane exhibit a perfect helicity exchange, and the helicity selections of the E <superscript>1</superscript> <subscript>2g</subscript> and A <subscript>1g</subscript> modes of the edge plane are eliminated or weakened. Our study provides references for phonon helicity selection of 2D layered materials represented by MoS <subscript>2</subscript> .