We report the enthalpy of oxygen vacancy formation in thin films of electron-doped SrTiO3, under different degrees of epitaxial stress. We demonstrate that both compressive and tensile strain decrease this energy at a very similar rate, and promote the formation of stable doubly ionized oxygen vacancies. Moreover, we also show that unintentional cationic vacancies introduced under typical growth conditions, produce a characteristic rotation pattern of TiO6 octahedra. The local concentration of oxygen vacancies can be modulated by an electric field with an AFM tip, changing not only the local electrical potential, but also producing a non-volatile mechanical response whose sign (up/down) can be reversed by the electric field.
@article{arxiv.1704.05620,
title = {Oxygen vacancies in strained SrTiO$_{3}$ thin films: formation enthalpy and manipulation},
author = {L. Iglesias and A. Sarantopoulos and C. Magen and F. Rivadulla},
journal= {arXiv preprint arXiv:1704.05620},
year = {2017}
}