Reconfigurable Oxide Nanoelectronics by Tip-induced Oxygen Vacancy Migration

Reconfigurable oxide nanoelectronics, enabled by conductive atomic force microscope (cAFM) lithography, have established complex oxide interfaces as a promising platform that harnesses emergent phenomena. However, this device fabrication process can only take place in the air, and devices decay simultaneously in the fabrication process under the "water cycle" mechanism, which posts ongoing challenges for optimizing device performance at mK temperatures. Here, we demonstrate a "waterless" cAFM lithography approach at LaAlO₃/SrTiO₃ interface that is compatible with vacuum and cryogenic environments. Through oxide interface engineering by optimizing oxygen vacancy migration, we achieve nonvolatile and reconfigurable cAFM control of nanoscale interfacial metal-insulator transition at mK temperatures with an ultrafine line resolution of 0.85 nm. This advancement enables in-situ reconfigurable device fabrication and concurrent characterization, significantly enhancing device optimization and yield. Our findings are supported by first-principles calculations and drift-diffusion modeling, which suggest that oxygen vacancy electromigration plays a key role in this "waterless" cAFM lithography.