Reconfigurable nonlinear photonic activation function for photonic neural network based on non-volatile opto-resistive RAM switch

摘要

Photonic neural network has been sought as an alternative solution to surpass the efficiency and speed bottlenecks of electronic neural network.Despite that the integrated Mach-Zehnder Interferometer(MZI)mesh can perform vector-matrix multiplication in photonic neural network,a programmable in-situ nonlinear activation function has not been proposed to date,suppressing further advancement of photonic neural network.Here,we demonstrate an efficient in-situ nonlinear accelerator comprising a unique solution-processed two-dimensional(2D)MoS2 Opto-Resistive RAM Switch(ORS),which exhibits tunable nonlinear resistance switching that allow us to introduce nonlinearity to the photonic neuron which overcomes the linear voltage-power relationship of typical photonic components.Our reconfigurable scheme enables implementation of a wide variety of nonlinear responses.Furthermore,we confirm its feasibility and capability for MNIST handwritten digit recognition,achieving a high accuracy of 91.6%.Our accelerator constitutes a major step towards the realization of in-situ photonic neural network and pave the way for the integration of photonic integrated circuits(PIC).