Energy-efficient neural network inference with microcavity exciton polaritons

We propose all-optical neural networks characterized by very high energy efficiency and performance density of inference. We argue that the use of microcavity exciton-polaritons allows to take advantage of the properties of both photons and electrons in a seamless manner. This results in strong optical nonlinearity without the use of optoelectronic conversion. We propose a design of a realistic neural network and estimate energy cost to be at the level of attojoules per bit, also when including the optoelectronic conversion at the input and output of the network, several orders of magnitude below state-of-the-art hardware implementations. We propose two kinds of nonlinear binarized nodes based either on optical phase shifts and interferometry or on polariton spin rotations.Ministry of Education (MOE)Published versionM.M. acknowledges support from National Science Center, Poland Grant No. 2017/25/Z/ST3/03032 under the QuantERA program. A.O. acknowledges support from National Science Center, Poland Grant No. 2016/22/E/ ST3/00045. R.M. acknowledges support from National Science Center, Poland Grant No. 2019/33/N/ST3/02019. B.P. acknowldges support from National Science Center, Poland Grant No. 2020/37/B/ST3/01657. K.T. acknowldges support from National Science Center, Poland Grant No. 2020/04/X/ST7/01379. T.L. acknowledges the support of the Singapore Ministry of Education, via the Academic research fund project MOE2019-T2-1-004. D.B. and D.S. acknowledge support from the project FISR2020- COVID, WaveSense (FISR2020IP_04324), and the PRIN 2017 InPhoPOL