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Taming nonequilibrium thermal fluctuations in subthreshold CMOS circuits

Nahuel Freitas*,†, Geremia Massarelli, Jeremy Rothschild, Dylan Keane, Ethan Dawe, Sewook Hwang, Akhil Garlapati†, and Trevor McCourt†,‡

  • Extropic Corporation, Cambridge, Massachusetts, USA

  • *Contact author: nfreitas@extropic.ai
  • †These authors contributed equally to this work.
  • ‡Contact author: trevor@extropic.ai
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Phys. Rev. Applied 25, 034061 – Published 18 March, 2026

DOI: https://doi.org/10.1103/5l2z-3f1h

Abstract

As CMOS technology scales down, thermal fluctuations increasingly impact circuit behavior, posing challenges to conventional circuit design. However, the inherent stochasticity introduced by thermal noise is now being explored as a potential resource in the emerging field of probabilistic computing. This work presents a fully CMOS experimental platform that enables direct control over its intrinsic thermal fluctuations. These devices function as programmable multivariate Gaussian samplers, offering a hardware primitive for energy-efficient stochastic computing and serving as an experimental platform for studies in electronic noise and stochastic thermodynamics.

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Corrections

3 April, 2026

Correction: A typographical error in the text following Fig. 2 has been fixed.

Article Text

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Phys. Rev. Applied 25, 034061– Published 18 March, 2026
  • Received 4 July 2025
  • Revised 16 January 2026
  • Accepted 12 February 2026
  • Corrected 3 April 2026
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