Optoelectronic memristive sensor with reconfigurable logic operation capability in ZnO/Nb:SrTiO3 heterojunction

The optoelectronic memristive sensor exhibits unique advantages due to its nonvolatile memory, low power consumption, and dynamic response to light signals. In this work, an interfacial type memristive sensor based on a ZnO/Nb:SrTiO3 heterojunction is fabricated, exhibiting stable resistive switching characteristics, multi-level storage capability, and long retention time. Light sensing measurements indicate that the device shows a self-powered photoresponse behavior and a persistent photoconductive effect upon exposure to 365 nm ultraviolet light. Furthermore, reconfigurable “OR” and “NIMP” logic operations under both light and electrical stimulation are implemented. Temperature dependent analysis of resistance reveals that the charge transport follows the space-charge-limited current mechanism in both high and low resistance states. Consequently, the resistance switching effect and the corresponding photoresponse can be attributed to the migration of oxygen vacancies coupled with electron trapping/de-trapping. This work highlights the potential of the ZnO/Nb:SrTiO3 heterojunction for applications in optoelectronic memristive sensors and programmable logic circuits.