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arXiv · 1509.08412

How the aggregation of oxygen vacancies in rutile based TiO$_{2-δ}$ phases causes memristive behavior

Wolfgang Heckel·Michael Wehlau·Sascha B. Maisel·Thomas Frauenheim·Jan M. Knaup·Stefan Müller
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Abstract

The results of a comprehensive and systematic ab-initio based ground-state search for the structural arrangement of oxygen vacancies in rutile phase TiO$_2$ provide new insights into their memristive properties. We find that O vacancies tend to form planar arrangements which relax into structures exhibiting metallic behavior. These meta-stable arrangements are structurally akin to, yet distinguishable from the Magnéli phase. They exhibit a more pronounced metallic nature, but are energetically less favorable. Our results confirm a clear structure-property relationship between segregated oxygen vacancy arrangement and metallic behavior in reduced oxides.

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Wolfgang Heckel, Michael Wehlau, Sascha B. Maisel, Thomas Frauenheim, Jan M. Knaup, Stefan Müller. 2015-11-20. How the aggregation of oxygen vacancies in rutile based TiO$_{2-δ}$ phases causes memristive behavior. https://doi.org/10.1103/physrevb.92.214104

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