Detailed theoretical analysis on nonlinear dynamic characteristics of tunable photonic spiking neuron based on optically pumped Spin-VCSEL

In this article, we proposed the use of optically pumped spin vertical-cavity surface-emitting laser (Spin-VCSEL) to create a photonic spiking neuron. We studied the dynamics of excitability and inhibitability under optical injection and analyzed the propagation characteristics of spiking information between unidirectionally-coupled Spin-VCSEL neurons. Our results demonstrated that by properly selecting parameters such as negative disturbance intensity from stimulus, pump ellipticity, and frequency detuning, Spin-VCSEL can achieve repeatable spiking output mode. Additionally, under certain conditions, it is possible to achieve inhibitory spiking output by selecting positive disturbance intensity from stimulus. By adjusting the duration and intensity of the disturbance, we can obtain controllable spiking responses for both excitable and inhibitory neurons. Furthermore, we found that under optimized injection strength, the spiking signal from the transmitter of Spin-VCSEL can be successfully propagated to the cascaded receiver with high quality. This work is meaningful because Spin-VCSEL offers new control dimensions such as pump ellipticity. Therefore, our study provides a valuable new choice for neuron construction of photonic spiking neural networks (PSNN).