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Josephson dynamics of two-dimensional Bose-Einstein condensates in a dual-core trap: Homogeneous, droplet-droplet, and vortex-vortex regimes

Sherzod R. Otajonov1,2 and Fatkhulla Kh. Abdullaev1,3

Phys. Rev. A 113, 043319 – Published 27 April, 2026

DOI: https://doi.org/10.1103/bphc-m85d

Abstract

The dynamics of a two-dimensional Bose-Einstein condensate mixture, loaded into a dual-core trap, when the beyond-mean-field effects are taken into account, are considered. The effects of quantum fluctuations are described by the Lee-Huang-Yang correction terms in the extended coupled Gross-Pitaevskii equations (GPE). The spatially uniform and inhomogeneous condensate cases are studied. In the first case, the parameter regimes associated with macroscopic quantum tunneling, macroscopic self-trapping, and revival-like localization dynamics are found. The Josephson oscillation frequencies for both the zero-phase and the π-phase modes are derived. As the total atom number is varied, the dynamics exhibit a nontrivial bifurcation structure: along the zero-phase branch, two successive pitchfork bifurcations generate bistability and hysteresis, while the π-phase branch shows a single pitchfork bifurcation. In the second case, the Josephson dynamics for quantum droplets and vortices are investigated. The analytical predictions for the oscillation frequencies of the atomic population between quantum droplets are found, and results are validated by direct numerical simulations of the system of coupled extended GPE. The existence of the Andreev-Bashkin nondissipative drag through simulations of droplet-droplet interactions is shown. The Josephson dynamics of vortex states are studied. It was found that vortices with topological charge S and sufficiently small particle number are typically unstable, breaking up into S+1 (and occasionally S+2) fundamental, nonvortical fragments, with the time to breakup increasing as the particle number grows. It is also found that unstable asymmetric vortices exhibit the splitting and/or crescentlike instability. For vortices with sufficiently large norms, long-time simulations confirm robust stability against small perturbations. In this stable regime, the properties of Josephson oscillations and Andreev-Bashkin-type entrainment for vortex states with charges S=1,2, and 3 are investigated.

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References (39)

  1. S. Raghavan, A. Smerzi, S. Fantoni, and S. R. Shenoy, Coherent oscillations between two weakly coupled Bose-Einstein condensates: Josephson effects, π oscillations, and macroscopic quantum self-trapping, Phys. Rev. A 59, 620 (1999).
  2. M. Albiez, R. Gati, J. Fölling, S. Hunsmann, M. Cristiani, and M. K. Oberthaler, Direct observation of tunneling and nonlinear self-trapping in a single bosonic Josephson junction, Phys. Rev. Lett. 95, 010402 (2005).
  3. T. D. Lee, K. Huang, and C. N. Yang, Eigenvalues and eigenfunctions of a Bose system of hard spheres and its low-temperature properties, Phys. Rev. 106, 1135 (1957).
  4. D. S. Petrov, Quantum mechanical stabilization of a collapsing Bose-Bose mixture, Phys. Rev. Lett. 115, 155302 (2015).
  5. D. S. Petrov and G. E. Astrakharchik, Ultradilute low-dimensional liquids, Phys. Rev. Lett. 117, 100401 (2016).
  6. Z. H. Luo, W. Pang, B. Liu, Y. Y. Li, and B. A. Malomed, A new form of liquid matter: Quantum droplets, Front. Phys. 16, 32201 (2021).
  7. G. Semeghini, G. Ferioli, L. Masi, C. Mazzinghi, L. Wolswijk, F. Minardi, M. Modugno, G. Modugno, M. Inguscio, and M. Fattori, Self-bound quantum droplets of atomic mixtures in free space, Phys. Rev. Lett. 120, 235301 (2018).
  8. I. Ferrier-Barbut, H. Kadau, M. Schmitt, M. Wenzel, and T. Pfau, Observation of quantum droplets in a strongly dipolar Bose gas, Phys. Rev. Lett. 116, 215301 (2016).
  9. A. Bardin, F. Lorenzi, and L. Salasnich, Quantum fluctuations in atomic Josephson junctions: The role of dimensionality, New J. Phys. 26, 013021 (2024).
  10. F. Kh Abdullaev, R. M. Galimzyanov, and A. M. Shermakhmatov, Effects of quantum fluctuations on macroscopic quantum tunneling and self-trapping of a BEC in a double-well trap, J. Phys. B 56, 165301 (2023).
  11. F. Kh Abdullaev, R. M. Galimzyanov, and A. M. Shermakhmatov, Beyond-mean-field effects in dynamics of BEC in the double-well potential, Eur. Phys. J. D 78, 118 (2024).
  12. P. Wysocki, K. Jachymski, G. E. Astrakharchik, and M. Tylutki, Josephson dynamics and localization revivals in ultradilute quantum liquids, Phys. Rev. A 110, 033303 (2024).
  13. Z. Y. Liu, A. C. Ji, and Q. Sun, Fluctuation-driven self-trapping in Bose-Bose mixtures, Phys. Rev. Res. 6, 013014 (2024).
  14. M. Pylak, F. Gampel, M. Płodzień, and M. Gajda, Manifestation of relative phase in dynamics of two interacting Bose-Bose droplets, Phys. Rev. Res. 4, 013168 (2022).
  15. F. Kh Abdullaev, R. M. Galimzyanov, and A. M. Shermakhmatov, Beyond mean-field effects in dynamics of Bose-Einstein condensate in two-core trap, Phys. Rev. A 112, 013306 (2025).
  16. S. R. Otajonov, F. Kh Abdullaev, and A. Shermaxmatov, Beyond mean-field effects in Josephson oscillations and self-trapping of Bose-Einstein condensates in two-dimensional dual-core traps, Chaos, Solitons Fractals 202, 117481 (2026).
  17. A. Bellettini, A. Richaud, and V. Penna, Massive-vortex realization of a bosonic Josephson junction, Phys. Rev. Res. 6, 043197 (2024).
  18. Z. Chen, Y. Li, and B. A. Malomed, Josephson oscillations of chirality and identity in two-dimensional solitons in spin-orbit-coupled condensates, Phys. Rev. Res. 2, 033214 (2020).
  19. F. Kh Abdullaev, M. Brtka, A. Gammal, and L. Tomio, Solitons and Josephson-type oscillations in Bose-Einstein condensates with spin-orbit coupling and time-varying Raman frequency, Phys. Rev. A 97, 053611 (2018).
  20. E. Shamriz, Z. Chen, and B. A. Malomed, Suppression of quasi two-dimensional quantum collapse in the attraction field by the Lee-Huang-Yang effect, Phys. Rev. A 101, 063628 (2020).
  21. Z. Lin, X. Xu, Z. Chen, Z. Yan, Z. Mai, and B. Liu, Two-dimensional vortex quantum droplets get thick, Commun. Nonlinear Sci. Numer. Simul. 93, 105536 (2021).
  22. G. H. dos Santos, L. F. Calazans de Brito, A. Gammal, and A. M. Kamchatnov, Supersolic flow past an obstacle in quasi-two-dimensional Lee-Huang-Yang fluid, Phys. Rev. A 112, 033318 (2025).
  23. B. Liu, H. F. Zhang, R. X. Zhong, X. L. Zhang, X. Z. Qin, C. Huang, Y. Y. Li, and B. A. Malomed, Symmetry breaking of quantum droplets in a dual-core trap, Phys. Rev. A 99, 053602 (2019).
  24. Z. Chen, Y. Li, B. A. Malomed, and L. Salasnich, Spontaneous symmetry breaking of fundamental states, vortices, and dipoles in two- and one-dimensional linearly coupled traps with cubic self-attraction, Phys. Rev. A 96, 033621 (2017).
  25. T. G. Skov, M. G. Skou, N. B. Jørgensen, and J. J. Arlt, Observation of a Lee-Huang-Yang fluid, Phys. Rev. Lett. 126, 230404 (2021).
  26. S. H. Strogatz, Nonlinear Dynamics and Chaos: With Applications to Physics, Biology, Chemistry, and Engineering (CRC, Boca Raton, FL, 2018).
  27. L. Albuch and B. A. Malomed, Transitions between symmetric and asymmetric solitons in dual-core systems with cubic-quintic nonlinearity, Math. Comput. Simul. 74, 312 (2007).
  28. C. Paré and M. Florjanczyk, Approximate model of soliton dynamics in all-optical couplers, Phys. Rev. A 41, 6287 (1990).
  29. S. R. Otajonov, E. N. Tsoy, and F. K. Abdullaev, Stationary and dynamical properties of one-dimensional quantum droplets, Phys. Lett. A 383, 125980 (2019); L. Lavoine and T. Bourdel, Beyond-mean-field crossover from one dimension to three dimensions in quantum droplets of binary mixtures, Phys. Rev. A 103, 033312 (2021).
  30. B. B. Baizakov, A. Bouketir, A. Messikh, A. Benseghir, and B. A. Pumarov, Variational analysis of flat-top solitons in Bose-Einstein condensates, Int. J. Mod. Phys. B 25, 2427 (2011); S. R. Otajonov, E. N. Tsoy, and F. K. Abdullaev, Variational approximation for two-dimensional quantum droplets, Phys. Rev. E 102, 062217 (2020); S. R. Otajonov, B. A. Umarov, and F. K. Abdullaev, Dynamics of quasi-one-dimensional quantum droplets in Bose-Bose mixtures, Chaos, Solitons Fractals 186, 115212 (2024).
  31. N. G. Vakhitov and A. A. Kolokolov, Stationary solutions of the wave equation in a medium with nonlinearity saturation, Radiophys Quantum Electron. 16, 783 (1973).
  32. A. F. Andreev and E. P. Bashkin, Three-velocity hydrodynamics of superfluid solutions, Sov. Phys. JETP 42, 164 (1975).
  33. J. Nespolo, G. E. Astrakharchik, and A. Recati, Andreev-Bashkin effect in superfluid cold gases mixtures, New J. Phys. 19, 125005 (2017).
  34. R. M. Caplan, Q. Hoq, R. Carretero-González, and P. G. Kevrekidis, Azimuthal modulational instability of vortices in the nonlinear Schrödinger equation, Opt. Commun. 282, 1399 (2009).
  35. Y. Li, Z. Chen, Z. Luo, C. Huang, H. Tan, W. Pang, and B. A. Malomed, Two-dimensional vortex quantum droplets, Phys. Rev. A 98, 063602 (2018).
  36. C. R. Cabrera, L. Tanzi, J. Sanz, B. Naylor, P. Thomas, P. Cheiney, and L. Tarruell, Quantum liquid droplets in a mixture of Bose-Einstein condensates, Science 359, 301 (2018).
  37. P. Cheiney, C. R. Cabrera, J. Sanz, B. Naylor, L. Tanzi, and L. Tarruell, Bright soliton to quantum droplet transition in a mixture of Bose-Einstein condensates, Phys. Rev. Lett. 120, 135301 (2018).
  38. N. Masalaeva, W. Kirkby, F. Ferlaino, and R. N. Bisset, Quantum vortex channels as Josephson junctions, arXiv:2602.01889.
  39. V. S. Shchesnovich, B. A. Malomed, and R. A. Kraenkel, Solitons in Bose-Einstein condensates trapped in a double-well potential, Physica D 188, 213 (2004).

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