Correlation between the transport properties, atomic structure and oxygen vacancies of perovskites thin films

We present a study of the role of the oxygen vacancies on the atomic structure and the transport properties of a 20 nm thick La0.7Ca0.3MnO3 thin film grown by the pulsed laser deposition method on a SrTiO3 (001) substrate. The results show that the manganite lattice can accommodate up to 13{\%} of oxygen vacancies maintaining high crystalline order. Under such conditions the atomic structure is characterized by the movement of the La/Ca cations to the perovskite regular position, by the absence of the MnO6 basal plane rotation, and by a cooperative tilting of the octahedra along the out-of-plane direction. The metal-to-insulator transition temperature decreases from 265K for the fully oxygenated sample to 28 K for the sample with 13{\%} of oxygen deficiency..