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arXiv · 1704.05620

Oxygen vacancies in strained SrTiO$_{3}$ thin films: formation enthalpy and manipulation

L. Iglesias·A. Sarantopoulos·C. Magen·F. Rivadulla
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Abstract

We report the enthalpy of oxygen vacancy formation in thin films of electron-doped SrTiO$_{3}$, 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 TiO$_6$ 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.

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L. Iglesias, A. Sarantopoulos, C. Magen, F. Rivadulla. 2017-04-19. Oxygen vacancies in strained SrTiO$_{3}$ thin films: formation enthalpy and manipulation. https://doi.org/10.1103/physrevb.95.165138

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