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Heterosymmetric states of rotating quantum droplets under confinement

S. Nikolaou1, G. M. Kavoulakis1,2, and M. Ögren2,3

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Phys. Rev. A 114, 033301 – Published 1 September, 2026

DOI: https://doi.org/10.1103/sh9r-k9rw

Abstract

We investigate the rotational response of confined two-dimensional quantum droplets, which emerge in a binary Bose mixture that is stabilized against collapse by beyond-mean-field effects. We consider both a harmonic and an anharmonic external confining potential. We go beyond the widely employed single-order-parameter model, maintaining separate order parameters for the two components, and calculating the lowest-energy state for various values of the angular momentum. For a population-balanced quantum droplet and sufficiently strong confinement, we find that for certain values of the angular momentum the droplet is excited in a “heterosymmetric” manner, with the two components carrying different vorticities. We additionally investigate the effects of a small population imbalance in the droplet. Apart from an energy increase associated with the population difference, the imbalance also lifts the double degeneracy of the heterosymmetric states, which characterizes the Z2-symmetric balanced droplet. The heterosymmetric mode is found to be favored by the energy term that captures the beyond-mean-field effects in the mixture.

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Phys. Rev. A 114, 033301– Published 1 September, 2026
  • Received 25 March 2026
  • Accepted 10 August 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. Funded by Bibsam.

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