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arXiv · 2508.15626

Direct energy dissipation measurements for a driven superfluid via the harmonic-potential theorem

Clara Tanghe·Senne Van Wellen·Kobe Vergaerde·Karel Van Acoleyen
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Abstract

We propose and experimentally demonstrate a method to directly measure energy dissipation for a linearly driven superfluid confined in a harmonic trap. The method relies on a perturbed version of the harmonic-potential theorem, according to which a potential perturbation - effectively acting as a stirrer - converts center-of-mass motional energy into internal energy. Energy conservation then enables a direct, quantitative determination of the dissipated energy from measurements of the macroscopic center-of-mass observables. Applying this method to a perturbed, driven Bose-Einstein condensate, we observe dissipation curves characteristic of superfluid flow, including a critical velocity that depends on the stirrer strength, consistent with previous studies. Our results are supported by mean-field simulations, which corroborate both the theoretical framework and the experimental findings.

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Clara Tanghe, Senne Van Wellen, Kobe Vergaerde, Karel Van Acoleyen. 2026-03-17. Direct energy dissipation measurements for a driven superfluid via the harmonic-potential theorem. https://doi.org/10.1103/v17d-68v7

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