Figure 4: Thickness dependent SERS of monolayer WS2 and splitting of 
mode at room temperature.
mode at room temperature.From: Surface enhanced Raman scattering of monolayer MX2 with metallic nano particles
(a) Raman spectra of monolayer WS2 with different thickness Ag NPs on top. (b) Enhancement factors as a function of the Ag NP thickness. (c) Raman splitting of the 
mode with different thickness Ag NPs on top of it. (d) IP1/IP0 and IP2/IP0 as a function of the Ag NP thickness induced strain.
