Integrated photonic neural network with on-chip backpropagation training - Nature

Nature, Published online: 18 March 2026; doi:10.1038/s41586-026-10262-8An integrated photonic deep neural network was trained end-to-end with on-chip gradient-descent backpropagation, and all linear and nonlinear computations were performed on a single photonic chip, resulting in a reliable performance despite on-chip errors and variations.