Figure 4.

A) Absorption spectra of RGO determined from transmission measurements with different polarizations. The polarizer angle effectively selects s and p-polarization, and one intermediate polarization is also shown. The symmetric and asymmetric modes from Fig. 3 are labeled as ν_s and ν_as, respectively. B) Square of the absorbance of RGO (unpolarized spectrum from Fig. 3A) overlaid with a linear dependence to show the intercept at 1500 cm⁻¹.