thin films

Gaining control over the concentration and distribution of cationic and anionic defects is a novel route to induce new functional properties in transition metal oxides. For the particular case of SrTiO₃ (STO), local manipulation of oxygen vacancies (V_O) in thin films plays a crucial role on the magnetic and thermoelectric properties of this relevant material.
The strontium vacancies (V_Sr) also could influence the structural properties of the STO thin films, changing the characteristic rotation pattern of the TiO₆ octahedra in order to accommodate the epitaxial strain.
In this work, we present the experimental determination of the enthalpy of formation, DH, and diffusion coefficient, D, of V_O in STO thin films, as a function of strain. Our results demonstrate that both, compressive and tensile strain, lead to a decrease of DH and an increase of D[1]. Additionally, we show the possibility to manipulate V_O using not only the external electric field produced by Atomic Force Microscopy, but also through the mechanical force exerted by the tip.
Regarding V_Sr, we observed that the presence of the V_Sr determine the rotation pattern of TiO₆ octahedra, which influences the anisotropic magneto-transport properties of the thin films[1].


[1]L. Iglesias et Al., Phys. Rev. B 95, 165138(2017)