Halide perovskite memristor with ultra-high-speed and robust flexibility for artificial neuron applications†
Abstract
Threshold switching (TS) memristor-based artificial neurons have been regarded as one of the promising solutions for constructing circuits of spiking neural networks (SNNs) due to their intrinsic similarity to biological neurons. Limited by their materials and process, current flexible TS memristors still face significant challenges in obtaining both a fast-operating speed and robust flexibility. This paper demonstrates flexible TS memristors with Au/organic–inorganic hybrid halide perovskite (OIHP)/Au/polyethylene naphthalate (PEN) structures by a low-cost solution process, which exhibit an ultrahigh switching speed (<35/90 ns) and a robust flexibility. The leaky integrate-and-fire dynamics and strength-modulated spike frequency response of the devices as artificial neurons are simulated through SPICE. The switching speed of the devices depending on the spike event processing ability and the energy efficiency of SNNs is analyzed. Inspired by the Na+ ion influx of biological neurons, an iodine (I−) vacancy migration model is established to clarify the working mechanism of the ultrahigh switching speed. The potential cause of their robust flexibility is also carefully studied by time-resolved photoluminescence (TRPL). This work provides a new method for exploiting high-performance flexible artificial neurons and energy-efficient SNNs.