Figure 3
Top panels: Comparison of experimentally measured external quantum efficiency spectra (dotted lines) for inverted (left) and standard (right) architecture PBDTTBTZT:PC71BM devices, with simulated EQE spectra (full lines) obtained using the simple model (see text). Bottom panels: spectral charge generation rate as a function of depth calculated using a transfer matrix model of photon absorption. In this figure the light enters the device from the bottom of the figure (0 nm on the y-axis). For each device architecture, the red block indicates the part of the active layer in which generated charges can be collected at short circuit, according to the model used here. Only charges generated within these regions contribute to the simulated EQE.
