Researchers from the University of Tokyo, including Yuma Nakamura, Tomoyuki Kubota, Yusuke Imai, Sumito Tsunegi, Hirofumi Notsu, and Kohei Nakajima, have developed a novel approach to improve the performance of physical computing systems, which could have significant implications for the energy sector. Their work, published in the journal Nature Communications, focuses on overcoming the challenges posed by noise and temporal fluctuations in physical computing substrates.
Physical computing leverages unconventional materials and systems to perform computations more efficiently than traditional digital methods, which often consume high amounts of energy. However, noise and temporal fluctuations in these physical systems can degrade computational performance. The researchers propose a solution called ensemble reservoir computing (ERC), which uses multiple spatially multiplexed systems to average out these disturbances.
The study demonstrates that ERC can eliminate temporal fluctuations and noise from dynamical states under certain conditions, restoring computational performance to levels seen in noise-free environments. Moreover, ERC not only mitigates these issues but also taps into computational capabilities that conventional reservoir computing (RC) overlooks. This enhancement was shown across various dynamical systems, including periodic, chaotic, and strange-nonchaotic systems, where ERC outperformed conventional RC.
To test the practical applicability of ERC, the researchers used energy-efficient spin-torque oscillators (STOs). They found that ERC maintained high performance even under realistic conditions where noise and temporal fluctuations coexist. In an error detection test, STOs with ERC achieved 99% accuracy, whereas conventional STO reservoirs with linear regression performed at chance levels. This highlights ERC’s robustness and potential for improving the performance of physical computing systems in real-world scenarios.
For the energy sector, this research could lead to more efficient and reliable computational systems for managing energy grids, optimizing renewable energy integration, and enhancing energy storage solutions. By reducing the energy consumption associated with digital computation, ERC could contribute to more sustainable and resilient energy infrastructures.
Source: Nakamura, Y., Kubota, T., Imai, Y., Tsunegi, S., Notsu, H., & Nakajima, K. (2023). Ensemble Reservoir Computing for Physical Systems. Nature Communications.
This article is based on research available at arXiv.

