Charge-localization effects in the infrared transmittance of layered perovskites

In a previous study it has been shown that the formation of charged superlattices in Ni-and Mn-based perovskites opens a gap in their infrared polaronic background. This signature of charge localization is here used to compare the behavior of the polaronic carriers in Sr2MnO4, La2NiO4+y, Nd2CuO4-y and Nd1.85Ce0.15CuO4-y. It is shown that, as the temperature decreases, the carriers tend to localize in the nickelate and the manganite, to slightly increase their mobility in both cuprates.