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arXiv · 2508.03825

One-dimensional quantum droplets under linear gravitational-like trap

Abstract

We investigate the influence of a constant and time-dependent linear gravitational-like potential on one-dimensional quantum droplets (QDs), governed by an extended GPE incorporating a repulsive cubic effective mean-field (EMF) term and an attractive quadratic beyond-mean-field (BMF) correction. Within a tailored external confinement, we analytically characterize the QDs wavefunction and derive the effective interaction contributions. Analogous to classical Newtonian dynamics, the falling velocity of the droplet within a finite domain is found to depend solely on the strength of the linear gravitational like potential, remaining independent of both the total atom number and the magnitude of EMF nonlinearity. When the linear potential is temporally modulated, deviations in the trajectory of the droplet emerge relative to the static case, indicating potential applicability in precision gravimetry. To further probe the dynamical coherence properties, we compute the Shannon entropy and the Wigner quasi-probability distribution. Both measures reveal distinct signatures of the constant and time varying linear potential, with the modulation strength directly influencing the phase-space localization and coherence structure of the droplet. Numerical simulations substantiate the stability of the analytical solutions, demonstrating their robustness. These findings suggest promising implications for quantum sensing and metrological applications using ultradilute quantum fluids.

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Saurab Das, Jayanta Bera, Ajay Nath. 2025-08-05. One-dimensional quantum droplets under linear gravitational-like trap. https://arxiv.org/abs/2508.03825

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