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arXiv · 2408.13129

Optical activation function using a metamaterial waveguide for an all-optical neural network

Yoshihiro Honda·Yuya Shoji·Tomohiro Amemiya
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Abstract

In this study, we experimentally demonstrated that the nonlinear optical coefficient of the original Si can be enhanced by incorporating a metamaterial structure into an existing silicon waveguide. The two-photon absorption coefficient enhanced by the metamaterial structure was 424 cm/GW, which is 1.2x10^3 times higher than that of Si. Using this metamaterial waveguide-based nonlinear optical activation function, we achieved a high inference accuracy of 98.36% in the handwritten character recognition task, comparable to that obtained with the ReLU function as the activation function. Therefore, our approach can contribute to the realization of more power-efficient and compact all-optical neural networks.

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Yoshihiro Honda, Yuya Shoji, Tomohiro Amemiya. 2024-08-23. Optical activation function using a metamaterial waveguide for an all-optical neural network. https://arxiv.org/abs/2408.13129

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