Analog optical computer for AI inference and combinatorial optimization.
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Peer-reviewed
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Abstract
Artificial intelligence (AI) and combinatorial optimization drive applications across science and industry, but their increasing energy demands challenge the sustainability of digital computing. Most unconventional computing systems1-7 target either AI or optimization workloads and rely on frequent, energy-intensive digital conversions, limiting efficiency. These systems also face application-hardware mismatches, whether handling memory-bottlenecked neural models, mapping real-world optimization problems or contending with inherent analog noise. Here we introduce an analog optical computer (AOC) that combines analog electronics and three-dimensional optics to accelerate AI inference and combinatorial optimization in a single platform. This dual-domain capability is enabled by a rapid fixed-point search, which avoids digital conversions and enhances noise robustness. With this fixed-point abstraction, the AOC implements emerging compute-bound neural models with recursive reasoning potential and realizes an advanced gradient-descent approach for expressive optimization. We demonstrate the benefits of co-designing the hardware and abstraction, echoing the co-evolution of digital accelerators and deep learning models, through four case studies: image classification, nonlinear regression, medical image reconstruction and financial transaction settlement. Built with scalable, consumer-grade technologies, the AOC paves a promising path for faster and sustainable computing. Its native support for iterative, compute-intensive models offers a scalable analog platform for fostering future innovation in AI and optimization.
Description
Acknowledgements: We acknowledge G. Mourgias-Alexandris and I. Haller for contributions to the first-generation AOC hardware; S. Jordan, B. Lackey, A. Barzegar, F. Hamze and M. Troyer for discussions about optimization problems and for providing us with the QUBO benchmarks (Wishart, Tile3D, RCDP); J. Cummins for contributions to medical image reconstruction; A. Grace for contributions to the AOC hardware; J. Westcott, N. Farrell and T. Burridge for the AOC mechanical parts; S. Y. Siew for help with microLEDs; M. Schapira and colleagues at Microsoft Research, Cambridge, UK, and S. Bramhavar from ARIA for discussions. N.G.B. acknowledges the support from HORIZON EIC-2022-PATHFINDERCHALLENGES-01 HEISINGBERG Project 101114978 and the support from Weizmann-UK Make Connection Grant 142568.
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1476-4687

