Ultrafast Electro-Optic Spiking Membrane III-V Lasers on Silicon Utilizing Integrated Optical Feedback

This paper summarizes various experimental results on the characterization of the novel spiking membrane lasers on SiO₂/Si and their spiking dynamics. The ultra-thin (<350-nm-thick) membrane III-V on SiO₂/Si structure results in a very high optical confinement factor which is suitable for both increasing processing speeds and minimizing power consumptions. Moreover, for spiking generation we rely on bi-modal dynamics based on integrated optical feedback, which is a more efficient approach than other methods that rely on (slower) carrier-photon dynamics. Based on this, we report the first (to the best of our knowledge) bi-modal spiking laser capable of producing spikes via electrical inputs, suitable for various multiplexing approaches. Aiming to go beyond the state-of-the-art, the list of achievements in the present work includes demonstrated novel electro-optic excitability using up to 60 GBaud electrical input pulses, spiking rates of more than 12.5 GHz, spikes pulse widths of ∼10 ps, static operating energies in the order of ∼1 pJ/spike, and threshold energies of few ∼100 fJ/spike. Noticeable spiking effect stability and reproducibility are also reported. We believe that these results pave the way towards future multi-neuron membrane photonic spiking neural networks and neuromorphic photonic systems-on-chip, offering enhanced processing speeds, scalability, and energy-efficiency for AI applications.