Superfluid memory effect

Kristan Jensen; Alfredo Pérez; Stefan Prohazka

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arXiv · 2608.31172

Superfluid memory effect

Kristan Jensen·Alfredo Pérez·Stefan Prohazka

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Abstract

We identify a memory effect produced by phonon scattering in a superfluid: a localized scattering event generates a far-field pressure pulse with vanishing time integral but a nonzero first temporal moment, corresponding to a permanent shift in a prepotential for the far-field velocity. The effect is controlled by the soft factor for phonon emission, including corrections from nonlinear dispersion. In superfluid $^4$He, scattering macroscopic phonon wave packets produces a signal whose estimated magnitude may lie within experimental reach, thereby providing a laboratory analogue of electromagnetic and gravitational memory.

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Kristan Jensen, Alfredo Pérez, Stefan Prohazka. 2026-08-31. Superfluid memory effect. https://arxiv.org/abs/2608.31172

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