Stable Propagation of Inhibited Spiking Dynamics in Vertical-Cavity Surface-Emitting Lasers for Neuromorphic Photonic Networks

Electrically Controlled Neuron-Like Spiking Regimes in Vertical-Cavity Surface-Emitting Lasers at Ultrafast Rates

“…The associated carrier dynamics of this injection locked-unlocked transition, that ultimately determine the achievable inter-spike intervals or recovery time, are faster than the carrier dynamics associated to the transitions between lasing and non-lasing regimes used in other SL-based approaches for optical neuronal models. Using the electricallycontrolled VCSEL neuronal model in this work we should be able to replicate the spike communication networks previously created using the all-optical stimulation approach [43,44]. This works new approach, with the additional benefit of being wavelength-independent, could hopefully be expanded into diverse networks of artificial VCSELs neurons capable of processing all-optical spikes similar to the brain.…”

“…In particular, VCSELs have attracted great research interest for use in neuromorphic photonics, given their inherent advantages, such as ultra-small footprint, low manufacturing cost, high-speed, potential for large scale integration and operation at telecommunication wavelengths, to name but a few [37,38]. The proposed use of VCSELs as artificial photonic neurons has seen the application of techniques such as polarization switching (PS) [39,40] and optical injection (OI) [26][27][28][29] [41][42][43][44][45][46] for the all-optical conversion of binary signals to spiking patterns. Perturbed OI has been used experimentally to demonstrate the controllable activation [41], and inhibition [42], of sub-ns excitable spike patterns in telecom-wavelength VCSELs with promising neuronal features.…”

“…interconnection of these photonic neuromorphic elements has also been explored with the successful communication of fast spiking dynamics in a cascaded transmitter-receiver VCSEL configuration [43,44], and with detailed theoretical studies of multiple mutual coupling configurations [48,49]. The behavioural similarities that can be drawn between the investigated VCSEL-based neuronal models and biological neurons are what allow us to pursue these devices as candidates for artificial photonic neurons.…”

Toward Neuromorphic Photonic Networks of Ultrafast Spiking Laser Neurons

“…Wavelength Experimental/ Numerical Spike activation via polarization switching [28,35] 1550 nm Experimental Spike activation via electrical bias stimulation [38] 1310 nm Experimental Spike activation via phase-modulated optical injection [29][30][31] 980 nm Experimental/ Numerical Spike activation via amplitudemodulated optical injection [37,[43][44] 1310 nm Experimental/ Numerical Spike inhibition via amplitudemodulated optical injection [39,43] 1310 nm Experimental/ Numerical Spike activation/inhibition via saturable absorber region [27,[47][48] 850 nm Numerical Networked/coupled spiking VCSELs [40][41][42]44] 1310 nm Experimental/ Numerical Nevertheless, to date the majority of works on SL-based photonic spiking neurons have focused on single devices. Yet, it is widely acknowledged that the implementation of interconnected architectures is needed to develop neuromorphic photonic systems for use in practical computing and Artificial Intelligence applications.…”

“…Moreover, VCSEL-Neurons operating at both short (e.g. 850 nm) [29][30][31] and long-wavelengths (1310 nm, 1550 nm) have been experimentally demonstrated [28] [37][38][39][40][41]. Specifically, using short-wavelength VCSEL-Neurons, the activation, storing and control of excitable spikes under phase-modulated optical injection has been reported [29][30][31].…”