Fig. 5: Electroabsorption spectra fitting.

a–e Measured second harmonic (2ω) EA signals (transmission mode) for different loading ratios (1 wt%, 10 wt%,40 wt%, 70 wt%, and 100 wt%) of Y6 in PVK fitted with Eq. (4). f, g Second harmonic (2ω) EA signals of 10 and 100 wt% ITIC in PVK fitted with Eq. (4). The red symbols represent the fitted region of the EA signal, which corresponds to the first Gaussian band of the thin film absorbance of Y6 and ITIC. The extracted Δµ (change in dipole moment) and Δp (change in polarizability) values of the different samples are shown in the figures.