Self-rectifying volatile memristor with ultrahigh rectification enabled by asymmetric oxide heterostructures

Volatile memristors hold promise for time-domain electronic functionalities beyond static memory, but their practical adoption is impeded by leakage currents, insufficient rectification, and unstable transient behaviors. Here, we report a self-rectifying volatile memristor based on a Pt/Ga2O3/indium gallium zinc oxide (IGZO)/Ti heterostructure. Asymmetric Schottky barriers yield an ultrahigh rectification ratio exceeding 7.9 × 107, effectively suppressing reverse leakage currents and providing intrinsic selector-like characteristics. Concurrently, defect-mediated transport and charge detrapping within the IGZO layer enable volatile resistive switching with spontaneous relaxation, yielding a millisecond-scale relaxation time and eliminating the need for external reset operations. These transient dynamics, manifesting as charge accumulation, threshold switching, and relaxation, reflect the device's intrinsic temporal response. The combination of extreme rectification and volatile behavior further allows the implementation of artificial neuron functionalities for neuromorphic computing.