So far we were using thickness gradients for the combinatorial optimization of solar cells, but now we are expanding the range of applications. We introduce microcavity resonating detectors that use the charge transfer absorption to obtain narrow band detection. These results, just published in Advanced Materials (DOI: 10.1002/adma.201702184) come from a collaboration with the group of Koen Vandewal in Dresden. As the central wavelength of detection depends on the thickness of the active layer, we showed that thickness gradients of the active layer can be used to fabricate miniature spectrophotometers.
By Zheng Tang, Zaifei Ma, Antonio Sánchez-Díaz, Sascha Ullbrich, Yuan Liu, Bernhard Siegmund, Andreas Mischok, Karl Leo, Mariano Campoy-Quiles, Weiwei Li and Koen Vandewal, Advanced Materials (2017)| DOI: 10.1002/adma.201702184