Fig. 2

Evolution of the vibration and optical spectra of the MoS2 monolayer under gating voltage and changes of Raman spectra of monolayer MoS2 at different gating voltage, Vg. a Gating tunability of vibration modes in monolayer MoS2. b The measured Raman intensity ratio as a function of gating voltage, Vg. Reflection at normal angle of incidence. c Comparison of relative reflection spectra at normal incidence for different Vg. d The reflectivity of Au/Si3N4/MoS2 hybrid waveguide nanostructure at normal incidence