All-optical spiking laser neuron integrated in generic InP photonic circuit technology.

Brain-inspired, neuromorphic devices implemented in integrated photonic hardware have attracted significant interest as part of efforts towards non-von Neumann computing paradigms that use the low-loss, high-speed, and parallel operations in optics. We present here the design and measurements of an all-optical spiking laser neuron that was realized for the first time on a generic InP photonic foundry platform, which may be a practical alternative to other semi-integrated photonic and electronic-based spiking neuron implementations. The measured device demonstrates excitability, nanosecond refractory period, and self-pulsating capabilities. We show that the device offers sufficient optical gain for incoming spikes, an essential feature for directly cascading neurons. In addition, we demonstrate multi-wavelength injection and excitability and discuss the possibilities of combining this device with other on-chip photonic devices. The reported characteristics are an improvement over the state-of-the-art, because the proposed device allows for direct on-chip cascading of neurons and weights, which is essential for future fully connected, multi-wavelength, all-optical photonic spiking neural networks.