Fig. 1. Spiking neuron model

Fig. 2. Experimental setup of photonic LIF neuron based on SOA^[44]

Fig. 3. Schematic of the symmetric photonic neuron with excitatory and inhibitory inputs^[44]

Fig. 4. Schematic diagram of photonic STDP based on SOA^[45]

Fig. 5. Implementation mechanism of photonic STDP based on SOA^[45]

Fig. 6. Implementation of an asynchronous spiking photonics neuron based on EAM^[47]

Fig. 7. Implementation of photonic STDP based on SOA and EAM^[48]

Fig. 8. Implementation of LIF neuron based on DFB-SA^[49-50]

Fig. 9. Implementation of photonic STDP based on DFB-LD^[52]

Fig. 10. Implementation of graphene excitable laser^[53-54]

Fig. 11. Temporal pattern recognition implemented by LIF neuron based on graphene excitable laser^[54]

Fig. 12. Self-recurrent bistable circuit implemented by LIF neuron based on graphene excitable laser^[54]

Fig. 13. Implementation of graphene excitable laser with excitatory and inhibitory inputs^[55]

Fig. 14. A schematic diagram of VCSEL-SA^[56]

Fig. 15. Photonic SNN for unsupervised arbitrary pulse pattern recognition based on VCSELs and VCSOAs^[59]

Fig. 16. Schematic diagram of photonic SNN for supervised learning classification task based on VCSELs-SA and VCSOAs^[60]

Fig. 17. Photonic spiking neuron based on microring resonator embedded with GST^[81]

Fig. 18. All-optical spiking neuron network based on PCM and microring resonators^[82]

Fig. 19. Perspective view of the hybrid graphene-on-silicon microring coupled with a silicon bus waveguide^[83]

Fig. 20. Photonic spiking neuron based on add-drop microring resonators^[84]