Abstract
Oscillator Ising machines (OIMs) and probabilistic bit (p-bit) platforms have emerged as promising non-Von Neumann paradigms for tackling hard computational problems. While OIMs realize gradient-flow dynamics, p-bit platforms operate through stochastic sampling. Although traditionally viewed as distinct approaches, this work presents a theoretically grounded framework for configuring OIMs as p-bit engines. We demonstrate that this functionality can be enabled through a novel interplay between first- and second harmonic injection to the oscillators. Our work identifies new synergies between the two methods and broadens the scope of applications for OIMs beyond combinatorial optimization problems to those that entail stochastic sampling. We further show that the proposed approach can be applied to other analog dynamical systems, such as the Dynamical Ising Machine.
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The data that support the findings of this study are available from the corresponding author upon request.
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Acknowledgements
We gratefully acknowledge Prof. Kerem Camsari for providing valuable insights on the sampling properties of p-bits. This material is based upon work supported in part by ARO award W911NF-24-1-0228 and National Science Foundation grants (#2422333, #2433871).
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E. M. Hasantha Ekanayake: Conceptualization (equal); Formal analysis (equal); Software (equal); Writing—original draft (equal); Writing—review and editing (equal). Nikhat Khan: Conceptualization (equal); Validation (equal); Software (equal); Writing—original draft (equal); Writing—review and editing (equal). Nikhil Shukla: Conceptualization (equal); Funding acquisition (lead); Supervision (lead); Validation (equal); Writing—review and editing (equal).
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Communications Physics thanks Corentin Delacour, Jérémie Laydevant, and the other anonymous reviewer(s) for their contribution to the peer review of this work.
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Ekanayake, E.M.H., Khan, N. & Shukla, N. Configuring oscillator Ising machines as P-bit engines. Commun Phys (2026). https://doi.org/10.1038/s42005-026-02492-z
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DOI: https://doi.org/10.1038/s42005-026-02492-z
