Fig. 9.

Schematics of the B&W architecture for neural networks. a The B&W architecture (bottom) shows parallels with the neuron model (top). Adapted with permission from [164], copyright 2014, OPG. b Concept of a B&W network with MRR arrays as the spectral filters. Adapted with permission from [165], copyright 2017, NPG. c–d Different mapping topologies for photonic neural networks, e.g., c feedforward network and d recurrent network. Adapted with permission from [174], copyright 2018, IEEE. e An optoelectrical architecture that performs a single convolution window. Adapted with permission from [175], copyright 2020, IEEE. f Conceptual layout of an optical patching scheme. Adapted with permission from [, copyright 2020, OPG176