Carbon quantum dots boosted resistive switching and magnetic properties in Co3O4-based memory devices

Abstract

Carbon quantum dots (CQDs) could create opportunities of modulating resistive switching behaviors due to their unique electrical performance. Here, CQDs are introduced to enhance switching uniformity and magnetic properties in Co3O4 thin film memory devices. Compared with the pure Co3O4-based device, the device with CQDs exhibited better performance, such as a reduced initialization voltage, uniform distribution of Set and Reset voltages, stable endurance behavior, and enhanced magnetization performance. The fitting results of current-voltage curves showed that the low-resistance states and high-resistance states of the devices obey Ohmic conduction and Schottky emission, respectively. The improvement in resistive switching properties is ascribed to the formation and rupture of confined conductive filaments due to that CQDs enhanced the local electric field, which can efficiently guide the filament growth and suppress the randomness of filament growth. Magnetization modulation associated with resistive switching involves in the variation of oxygen vacancies concentration and the conversion between Co2+ and Co3+. The present study exhibits an effective path to enhance resistive switching and magnetic properties, which shows promising application to design multifunctional electro-magnetic integrated devices.