Pr0.5Ca0.5MnO3 thin films deposited on LiNbO3 substrates

Thin films of Pr0.5Ca0.5MnO3 have been deposited on z-cut LiNbO3 by pulsed laser ablation. The Xray diffraction measurements showed that the films have grown highly oriented on LiNbO3, with a pseudocubic (111) preferred growth direction. The thicknesses of the films, measured by low angle X-ray reflectivity, are between 13 and 140 nm. Their electrical resistivity present a semiconducting-like behaviour with an anomaly around 240 K, that corresponds to the charge ordering transition. The temperature of the transition (TCO) was estimated from ln ρ vs. (1/T) plots. The charge ordering temperature was found to be dependent on the strain induced by the lattice mismatch on the films.