Resistive switching localization and tuning via selective ion irradiation*

Various materials exhibit resistive switching (RS), a useful feature which lends well to the development of novel bioinspired electronic devices, notably artificial neurons and synapses for neuromorphic computing. This effect often manifests itself through the percolation of conducting filaments or the formation of transverse barriers. The location and switching parameters of RS are often impacted by inherent material defects which pose a challenge for scalability. By selectively engineering defects in VO_x and LSMO using a focused ion beam, we report a novel method for locally tuning the electronic properties (i.e. conductivity and metal-insulator transition temperature) of a material and by extension, controlling the location and geometry of RS. In addition to confining the conducting filament to the irradiated region, we observe a greater than 3 orders of magnitude reduction in RS power. Our work demonstrates that local ion irradiation impacts the electronic distribution and structure of a material, and is an efficient tool for fine-tuning material properties related to RS. This offers promising avenues for new energy-efficient biomimetic circuitry.