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  • Open Access

Nonequilibrium Equation of State for a Turbulent 2D Bose Gas

Yi Jiang*, Nikolai Maslov*, Andrey Karailiev, Christoph Eigen, Martin Gazo†, and Zoran Hadzibabic

  • *These authors contributed equally to this work.
  • †Contact author: mg816@cam.ac.uk
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Phys. Rev. Lett. 137, 203401 – Published 10 November, 2026

DOI: https://doi.org/10.1103/lh2x-jn4m

Abstract

Nonequilibrium equations of state can provide an effective thermodynamiclike description of far-from-equilibrium systems. We experimentally construct such an equation for a direct energy cascade in a turbulent two-dimensional Bose gas. Our homogeneous gas is continuously driven on a large length scale and, with matching dissipation on a small length scale, exhibits a nonthermal but stationary power-law momentum distribution. Our equation of state links the cascade amplitude with the underlying scale-invariant energy flux, and can, for different drive strengths, gas densities, and interaction strengths, be recast into a universal power-law form using scalings consistent with the Gross-Pitaevskii model.

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Outline

Information

Phys. Rev. Lett. 137, 203401– Published 10 November, 2026
  • Received 12 February 2026
  • Revised 12 July 2026
  • Accepted 24 September 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

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