Experimental Robust Spontaneous Synchronizations in Coupled NbO_x Oscillation Neurons for Unconventional Computing

In this brief, we demonstrate experimentally achieved oscillation dynamics in coupled NbOx thresholds witch (TS)-based oscillation neurons (ONs). We first show the challenges in observing oscillation caused by devicevariability, which is further validated through HSPICE simulations. To obtain robust oscillation response, a reliable TS developed via atomic layer deposition for conformal NbOx is introduced. By developing coupled NbO(x )ONs using acoupling resistor (RC), the out-of-phase synchronizationis demonstrated owing to the weak connection. Moreover,we achieve a transition to in-phase synchronization as the coupling strength increases, showing an inverse relation-ship with the magnitude of R-C. Based on these results,oscillatory neural networks, where multiple NbO(x )ONs arefully connected, are examined to execute pattern recognition via MATALB simulations