  Key pre-synaptic and post-synaptic biological functions have been
successfully implemented in various hardware systems. A noticeable example are
neuronal networks constructed from memristors, which are emulating complex
electro-chemical biological dynamics such a neuron's efficacy and plasticity.
Neurons are highly active cells, communicating with chemical and electrical
stimuli, but also emit light. These photons are suspected to be a complementary
vehicle to transport information across the brain. Here, we show that a
memristor also releases photons akin to the production of neuronal light.
Critical attributes of so-called biophotons such as self-generation, origin,
stochasticity, spectral coverage, sparsity and correlation with the neuron's
activity are replicated by our solid-state approach. Our findings further
extend the emulating capability of a memristor to encompass neuronal biophoton
emission and open the possibility to construct a bimodal electro-optical
platform with the assistance of atomic-scale devices capable of handling
electrons and photons as information carriers.
