Benjamin Lefler1,William Postiglione2,Chris Leighton2,Steven May1
Drexel University1,University of Minnesota Twin Cities2
Benjamin Lefler1,William Postiglione2,Chris Leighton2,Steven May1
Drexel University1,University of Minnesota Twin Cities2
Heteroanionic perovskites have attracted attention as a family of materials with a wide range of tunable magnetic, optical, and electronic properties. While such materials have largely been studied in bulk form, epitaxial films offer numerous opportunities to study and utilize heteroanionic materials due to their minimal volume allowing for fast reaction times, planar geometry, and ability to be patterned and fabricated into device structures. In recent work, we produced heterostructured films with lateral SrFeO<sub>3-δ</sub>/SrFeO<sub>2</sub>F patterns through lithographic masking and fluorination topochemistry. In this work, we demonstrate how these patterned structures can be dynamically altered with external stimuli. SrFeO<sub>3-δ</sub> films support room-temperature reversible switching behavior from metal to insulator with varied oxygen deficiency (0≤δ≤0.5) through ion gel gating, behavior that we confirm in monolithic films. In contrast, we demonstrate the robustness of insulating SrFeO<sub>2</sub>F films against ion gating redox chemistry through structural and optical characterization as a function of gate bias. We leverage these materials properties to enable voltage-controlled switchable patterned properties in the oxide/oxyfluoride structures. Namely, we report on the use of ion gating to reversibly interconvert an insulator-insulator (SrFeO<sub>2.5</sub>/SrFeO<sub>2</sub>F) pattern to a metal-insulator (SrFeO<sub>3-δ</sub>/SrFeO<sub>2</sub>F) pattern as a platform for electric field tuning of optical gratings or systems with high electrical anisotropy.<br/>This work is support by the National Science Foundation (grant CMMI-2001888). Work at UMN is supported by NSF MRSEC (DMR-2011401).