Leaky Integrate‐and‐Fire Mechanism in Exciton–Polariton Condensates for Photonic Spiking Neurons

This paper introduces a new approach to neuromorphic photonics in whichmicrocavities exhibiting strong exciton–photon interaction may serve asbuilding blocks of optical spiking neurons. The experimental resultsdemonstrate the intrinsic property of exciton–polaritons to resemble the LeakyIntegrate-and-Fire (LIF) spiking mechanism. It is shown that exciton–polaritonmicrocavities when non-resonantly pumped with a pulsed laser exhibit leakyintegration due to relaxation of the excitonic reservoir, threshold-and-firemechanism due to transition to Bose–Einstein Condensate (BEC), andresetting due to stimulated emission of photons. These effects, evidenced inphotoluminescence characteristics, arise within sub-ns timescales. Thepresented approach provides means for ultrafast processing of spike-like laserpulses with energy efficiency at the level below 1 pJ per spike.