Resistive Switching Characteristics of PPX-Based Memristors with PbTe Nanoparticles under Photoexcitation

The structural and memristive properties of layered Cu/PPX–PbTe/ITO samples based on parylene (poly-p-xylylene, PPX) containing PbTe nanoparticles are studied. An unusual light-induced effect on the resistive switching (RS) behavior is observed: in the high-resistance state (HRS), the memristor’s conductivity increases under illumination, whereas in the low-resistance state (LRS), negative photoconductivity (i.e., a noticeable decrease in conductivity) is observed during cyclic RS. A qualitative model is proposed that describes the switching mechanism with and without optical excitation. The RS specifications and their tunability by illumination demonstrate the potential of hybrid PPX-based memristors for use as sensory and synaptic elements in the development of neuromorphic vision systems.