Resistive switching and magnetic modulation based on graphene oxide quantum dot-doped amorphous TiO₂ composites

The rapid expansion of data-intensive applications in the AI era necessitates innovative memory technologies that offer high-density storage and in-memory processing. In this study, we introduce graphene oxide quantum dots (GQDs) doped amorphous TiO₂ (a-TiO₂) as a dielectric layer in resistive random access memory (RRAM). This approach significantly enhances resistive and magnetic switching performance while enabling more stable four-state storage. The fabricated Ag/GQDs:a-TiO₂/ITO device exhibits comparable endurance cycles (500 cycles) and retention time (12,000 s) to the undoped counterpart (Ag/a-TiO2/ITO), but with lower operating voltages (SET: 0.28 V, RESET: -0.25 V) and significantly improved operational stability(~80% reduced variability). Notably, the magnetic variation ratio of the fabricated device increases to 5.7 (compared to 2.96 for Ag/a-TiO₂/ITO), indicating that the presence of GQDs effectively enables electric field regulation of magnetism in RRAM. Material characterizations confirm the incorporation of GQDs into TiO₂ films, and the modulation of resistance and magnetism via electric field is primarily attributed to oxygen vacancies (VOs), which establish a resistive-magnetic synergistic coupling. This study provides a scalable approach for fabricating high-performance, multifunctional memory devices, thereby enabling the development of next-generation neuromorphic and spintronic systems.