Raman tensor of layered MoS₂

Raman tensors, one of the basic physical properties of ${{\rm MoS}_2}$MoS₂, are rarely reported. Here, angle-resolved polarized Raman scatterings on basal and cross planes of layered ${{\rm MoS}_2}$MoS₂ were carried out using the geometry configuration of parallel polarization, and the Raman tensors of three optical vibration modes were systematically studied. As a polar vibration mode, the differential polarizability of the ${{\rm A}_{1{\rm g}}}$A_1g mode corresponding to the Raman tensor along the $c$c direction is larger than that along the $a$a direction. In addition, it is also larger than that formed by ${{\rm E}_{2{\rm g}}}$E_2g and ${{\rm E}_{1{\rm g}}}$E_1g modes. All the experimental results above are beneficial to the understanding of inelastic light-scattering process of ${{\rm MoS}_2}$MoS₂.