Photo-Modulated Resistive Switching in GO-Doped In ₂ O ₃ /TiO ₂ Memristors for Artificial Synapse Applications

A bilayer resistive random-access memory (ReRAM) device is developed using a high-resistance TiO 2 bottom layer and a high-mobility In 2 O 3 top layer doped with graphene oxide (GO). Metal oxides are selected for their structural versatility and tunable electronic properties, while GO is incorporated to enhance the photoresponsivity and electrical performance. The switching behavior is analyzed by varying the GO concentration in the active layer. The device with 0.5% GO exhibits the most stable and distinct resistive switching, showing a clear hysteresis loop and an on/off ratio exceeding three orders of magnitude. Due to the strong absorption of visible light by GO, the device also demonstrates significant photoinduced modulation of its electrical characteristics. Integration with a thin-film transistor confirms its compatibility with standard digital circuitry. The combination of resistive switching and optical sensitivity suggests the potential of the proposed GO-doped oxide bilayer ReRAM structure for multifunctional and nonvolatile memory applications in advanced electronics.