Voltage Control of Patterned Metal/Insulator Properties in Oxide/Oxyfluoride Lateral Perovskite Heterostructures via Ion Gel Gating

Abstract

Abstract Dynamic control of patterned properties in perovskite oxide films can enable new architectures for electronic, magnetic, and optical devices. In this study, it is shown that SrFeO 3‐δ /SrFeO 2 F laterally‐heterostructured films enable voltage‐controlled tunable and reversible metal‐insulator patterned properties using room‐temperature ion gel gating. Specifically, SrFeO 3‐δ film regions can be toggled between insulating H x SrFeO 2.5 and metallic SrFeO 3 by electrochemical redox, while SrFeO 2 F regions remain robustly insulating and are unaffected by ion gel gating. Various gating architectures are also compared and establish the advantages of employing a conductive substrate as the contacting electrode, as opposed to at the film surface, thereby achieving complete and reversible reduction and oxidation among SrFeO 3‐δ , H x SrFeO 2.5 , and SrFeO 3 . This approach to voltage‐modulated patterned electronic, optical, and magnetic properties should be broadly applicable to oxide materials amenable to fluoridation, and potentially other forms of anion substitution.