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arXiv · 2003.11583

Nanophotonic spin-glass for realization of a coherent Ising machine

Yoshitomo Okawachi·Mengjie Yu·Jae K. Jang·Xingchen Ji·Yun Zhao·Bok Young Kim·Michal Lipson·Alexander L. Gaeta
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Abstract

The need for solving optimization problems is prevalent in a wide range of physical applications, including neuroscience, network design, biological systems, socio-economics, and chemical reactions. Many of these are classified as non-deterministic polynomial-time (NP) hard and thus become intractable to solve as the system scales to a large number of elements. Recent research advances in photonics have sparked interest in using a network of coupled degenerate optical parametric oscillators (DOPO's) to effectively find the ground state of the Ising Hamiltonian, which can be used to solve other combinatorial optimization problems through polynomial-time mapping. Here, using the nanophotonic silicon-nitride platform, we propose a network of on-chip spatial-multiplexed DOPO's for the realization of a photonic coherent Ising machine. We demonstrate the generation and coupling of two microresonator-based DOPO's on a single chip. Through a reconfigurable phase link, we achieve both in-phase and out-of-phase operation, which can be deterministically achieved at a fast regeneration speed of 400 kHz with a large phase tolerance. Our work provides the critical building blocks towards the realization of a chip-scale photonic Ising machine.

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BibTeXRIS

Yoshitomo Okawachi, Mengjie Yu, Jae K. Jang, Xingchen Ji, Yun Zhao, Bok Young Kim, Michal Lipson, Alexander L. Gaeta. 2020-03-25. Nanophotonic spin-glass for realization of a coherent Ising machine. https://doi.org/10.1038/s41467-020-17919-6

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