Modeling of thermal coupling in VO2-based oscillatory neural networks

In this study, we have demonstrated the possibility of using the thermal coupling to control the dynamics of operation of coupled VO2 oscillators. Based on the example of a 'switch-microheater' pair, we have explored the synchronization and dissynchronization modes of a single oscillator with respect to an external harmonic heat impact. The features of changes in the spectra are shown, in particular, the effect of the natural frequency attraction to the affecting signal frequency and the self-oscillation noise reduction effects at synchronization. The time constant of the temperature effect for the considered system configuration is in the range 7-140 mu s, which allows operation in the oscillation frequency range of up to similar to 70 kHz. A model estimate of the minimum temperature sensitivity of the switch is delta T-switch similar to 0.2 K, and the effective action radius R-TC of the switch-to-switch thermal coupling is not less than 25 mu m. Nevertheless, as the simulation shows, the frequency range can be significantly extended up to the values of 1-30 GHz if using nanometer-scale switches (heaters).