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arXiv · 2302.00793

Inverse-designed low-index-contrast structures on silicon photonics platform for vector-matrix multiplication

Vahid Nikkhah·Ali Pirmoradi·Farshid Ashtiani·Brian Edwards·Firooz Aflatouni·Nader Engheta
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Abstract

Inverse-designed Silicon photonic metastructures offer an efficient platform to perform analog computations with electromagnetic waves. However, due to computational difficulties, scaling up these metastructures to handle a large number of data channels is not trivial. Furthermore, a typical inverse-design procedure utilizes a small computational domain and therefore tends to employ resonant features to achieve its objectives. This results in structures that are narrow-bandwidth and highly sensitive to fabrication errors. Here, we employ a 2D inverse-design method based on the effective index approximation with a low-index contrast constraint. This results in compact amorphous lens systems which are generally feed-forward and low-resonance. We designed and experimentally demonstrated a vector-matrix product for a 2 x 2 and a 3 x 3 matrix. We also designed a 10 x 10 matrix using the proposed 2D computational method. These examples demonstrate that these techniques have the potential to enable larger-scale wave-based analog computing platforms.

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BibTeXRIS

Vahid Nikkhah, Ali Pirmoradi, Farshid Ashtiani, Brian Edwards, Firooz Aflatouni, Nader Engheta. 2023-02-01. Inverse-designed low-index-contrast structures on silicon photonics platform for vector-matrix multiplication. https://doi.org/10.1038/s41566-024-01394-2

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