Ferroelectric Topologically Configurable Multilevel Logic Unit.

Multilevel devices demonstrating switchable polarization enable us to efficiently realize neuromorphic functionalities including synaptic plasticity and neuronal activity. Here we propose using the ferroelectric logic unit comprising multiple nanodots disposed between two electrodes and coated by the dielectric material. We devise the integration of the ferroelectric logic unit, providing topologically configurable non-binary logic into a gate stack of the field-effect transistor as an analog-like device with resistive states. By controlling the charge of the gate, we demonstrate the various routes of the topological switchings between different polarization configurations in ferroelectric nanodots. Switching routes between different logic levels are characterized by hysteresis loops with multiple branches realizing specific interconnectivity regimes. The switching between different types of hysteresis loops is achieved by the variation of external fields and temperature. The devised ferroelectric multilevel devices provide a pathway toward the novel topologically-controlled implementation of discrete synaptic states in neuromorphic computing.