Li-Doped MgO-Based Memristor for a Biomimetic Nociceptor

Owing to the resistance switching behavior, memristors have been proven to have significant potential applications for memories and biological nociceptor simulation. Oxygen vacancy is one of the key factors influencing the resistance switching behavior of oxide-based memristors, and its concentration significantly impacts both the switching voltage and the cycling stability of the memristor. In this study, the concentration of oxygen vacancy is synergistically modulated by introducing Li doping into MgO as well as an AlOx interlayer by using Al as the top electrode. The effects of different Li-doping concentrations on the performance of the MgO-based memristors are investigated. It is found that a moderate amount of Li doping optimizes the oxygen vacancy concentration of MgO, thereby enhancing its cycling stability and enabling a low SET voltage. The device exhibits a retention of 104 s at 358 K and is capable of operating at temperatures as low as 100 K. The resistance switching mechanism of the device assisted by the AlOx interlayer is discussed. The synaptic plasticity, including long-term potentiation/depression, paired-pulse facilitation, and spike-timing-dependent plasticity, is investigated. Biological nociceptor behaviors, such as threshold, relaxation, and sensitization, have been successfully simulated by the Li-doped MgO-based memristor. These studies not only offer alternative approaches for designing future electronic devices but also serve as a reference for utilizing memristors in bionic applications.