Resistive Coupling of Bistable Resistor-Based Oscillators for Oscillatory Neural Network

An oscillatory neural network (ONN) is demonstrated by coupling a set of bistable resistor-based oscillators (birillators) through a coupling resistor ( ${R}_{\text {C}}$ ). Each birillator is composed of a nonlinear bistable resistor (biristor) and a load resistor ( ${R}_{\text {L}}$ ), which are connected in series. The synchronization behavior of oscillations among the resistively coupled birillators varies according to ${R}_{\text {C}}$ . When an external sine-wave signal was applied to the resistively coupled birillators, the phase of the oscillations was binarized by second-harmonic injection locking (SHIL). These coupled birillators with SHIL solved combinatorial optimization problems.