Oscillation characteristics based on VO2 volatile memristor. a) Schematic diagram of the oscillation neuron. b) Oscillation frequency as a function of load resistance (RL) with different input voltages (4, 5, 6 V). c) Oscillation frequency as a function of input voltage (Vin) with different load resistors (3.0, 3.5, 4.0, 4.5 kΩ). d) Neuronal response of the oscillation neuron under a constant bias voltage (5 V, 20 μs) and the influence of varying resistance (RL). The output frequencies are 0.9, 0.7, 0.55, and 0.35 MHz at RL of 3.0, 3.6, 4.2, 4.8 kΩ, respectively. e) Neuronal response of the oscillation neuron in series with a fixed resistance (RL=4 kΩ) and the influence of varying input voltage (Vin). The output frequencies are 0.45, 0.65, 0.8, and 0.9 MHz at Vin of 4.2, 4.8, 5.4, and 6.0 V, respectively.