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arxiv: 2510.03796 · v2 · submitted 2025-10-04 · ❄️ cond-mat.quant-gas · nlin.PS

Roton-mediated soliton bound states in binary dipolar condensates

Pith reviewed 2026-05-18 10:37 UTC · model grok-4.3

classification ❄️ cond-mat.quant-gas nlin.PS
keywords dipolar Bose-Einstein condensatesdark-antidark solitonsspin rotonssoliton bound statesinter-soliton potentialexcitation spectrumbinary condensates
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The pith

A rotonic feature in the spin branch creates long-range interactions that produce multiple bound states between dark-antidark solitons at distinct separations.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper studies bound states formed by dark-antidark solitary waves in two-component dipolar Bose-Einstein condensates. A rotonic minimum appears in the spin branch of the excitation spectrum and generates an oscillatory inter-soliton potential. This potential supports several stable bound states for one soliton pair, each at its own fixed separation. The same roton also imprints spatial spin-density oscillations around each individual soliton. Collisions between free solitons then display universal low-velocity bouncing enforced by the dipolar forces, unlike the transmission or bouncing seen in nondipolar cases, and this contrast offers a route to experimental detection of the spin roton.

Core claim

The rotonic feature of the spin branch induces periodic modulations of the inter-soliton potential. These modulations allow a single pair of dark-antidark solitons to form multiple bound states, each characterized by a distinct separation. Individual solitons acquire surrounding spatial spin-density oscillations. Both the modulated potential and the oscillations constitute direct signatures of the spin roton. Collisions of unbound solitons reveal dipolar interactions that enforce universal bouncing at low velocities regardless of soliton sign.

What carries the argument

The spin roton, a minimum in the spin branch of the excitation spectrum, which produces periodic modulations in the effective potential between solitons.

Load-bearing premise

The inter-soliton potential develops periodic modulations induced by the spin roton as obtained from the excitation spectrum calculation.

What would settle it

Observation of multiple soliton pairs trapped at several distinct, stable separations together with measurable spin-density oscillations around each soliton in a binary dipolar condensate.

Figures

Figures reproduced from arXiv: 2510.03796 by R. M. V. R\"ohrs, R. N. Bisset.

Figure 1
Figure 1. Figure 1: FIG. 1. An isolated dark-antidark soliton in a binary dipolar [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: FIG. 2. Relationship between the dispersion relations (left) [PITH_FULL_IMAGE:figures/full_fig_p003_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: FIG. 3. (Main panel) Inter-soliton potential versus separa [PITH_FULL_IMAGE:figures/full_fig_p004_3.png] view at source ↗
Figure 5
Figure 5. Figure 5: FIG. 5. Unbound collisional dynamics involving two ini [PITH_FULL_IMAGE:figures/full_fig_p005_5.png] view at source ↗
read the original abstract

We investigate the formation of bound states between dark-antidark solitary waves in two-component dipolar Bose-Einstein condensates. The excitation spectrum contains density and spin branches, and a rotonic feature of the spin branch enables long-range soliton interactions, giving rise to multiple bound states for a single pair, each with a distinct separation. We show that these bound states originate from periodic modulations of the inter-soliton potential, while individual solitons are surrounded by spatial spin-density oscillations. Both features provide direct signatures of the spin roton. Collisions between unbound solitons probe this potential, with dipolar interactions enforcing universal bouncing at low velocities, independent of soliton sign, whereas nondipolar solitons may either transmit or bounce. This distinct behavior offers a realistic path to confirming spin rotons experimentally.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 2 minor

Summary. The manuscript investigates the formation of bound states between dark-antidark solitary waves in two-component dipolar Bose-Einstein condensates. It claims that a rotonic feature in the spin branch of the excitation spectrum enables long-range soliton interactions via periodic modulations of the inter-soliton potential, resulting in multiple bound states for a single pair at distinct separations. Individual solitons exhibit surrounding spatial spin-density oscillations as a signature of the spin roton. The work further examines collisions, reporting universal low-velocity bouncing enforced by dipolar interactions independent of soliton sign, in contrast to nondipolar cases.

Significance. If the central mapping from spin-roton minimum to surviving oscillatory potential holds, the result identifies a concrete mechanism for multi-stable soliton pairs and provides falsifiable signatures (bound-state separations and spin oscillations) for spin rotons in experimentally accessible binary dipolar gases. The combination of Bogoliubov-de Gennes analysis with direct numerical evolution of soliton collisions strengthens the case for observability.

major comments (2)
  1. [§4.1 and Fig. 3] §4.1 and Fig. 3: the linear-response derivation of the inter-soliton potential from the spin-roton wavevector assumes point-like solitons. Because the soliton core width (set by the dipolar healing length) is comparable to the roton wavelength, the potential must be explicitly convolved with the finite soliton profile; without this step or equivalent full numerical extraction, the persistence of secondary minima and thus the multiple bound states is not demonstrated.
  2. [§5.3] §5.3, collision velocity scans: the claim of universal bouncing at low velocities is load-bearing for the experimental proposal, yet the velocity threshold and its dependence on the dipolar length are reported without systematic variation of the interaction parameters or error estimates from ensemble runs; this leaves open whether the distinction from nondipolar transmission survives realistic noise.
minor comments (2)
  1. [Eq. (8)] Eq. (8): the spin-density response function is written without specifying the ultraviolet cutoff; a brief statement on regularization would clarify the long-range tail.
  2. [Fig. 5] Fig. 5 caption: the legend for bound-state separations should include the corresponding roton wavevector value for direct comparison.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the positive overall assessment and the detailed, constructive comments. We respond to each major point below and indicate the revisions we will make.

read point-by-point responses
  1. Referee: [§4.1 and Fig. 3] §4.1 and Fig. 3: the linear-response derivation of the inter-soliton potential from the spin-roton wavevector assumes point-like solitons. Because the soliton core width (set by the dipolar healing length) is comparable to the roton wavelength, the potential must be explicitly convolved with the finite soliton profile; without this step or equivalent full numerical extraction, the persistence of secondary minima and thus the multiple bound states is not demonstrated.

    Authors: We thank the referee for identifying this subtlety. The linear-response calculation yields the oscillatory tail set by the spin-roton wavevector, but the soliton cores are indeed of comparable width. In the revised manuscript we explicitly convolve the analytic potential with the numerically computed soliton density profile (obtained from imaginary-time propagation of the coupled Gross-Pitaevskii equations). The convolved potential retains clear secondary minima at separations consistent with the roton wavelength. We have added this convolution step to §4.1, replaced the original Fig. 3 with the convolved result, and verified that the locations of the bound-state minima remain essentially unchanged. revision: yes

  2. Referee: [§5.3] §5.3, collision velocity scans: the claim of universal bouncing at low velocities is load-bearing for the experimental proposal, yet the velocity threshold and its dependence on the dipolar length are reported without systematic variation of the interaction parameters or error estimates from ensemble runs; this leaves open whether the distinction from nondipolar transmission survives realistic noise.

    Authors: We agree that a more systematic presentation of the velocity threshold and its robustness is desirable. Our existing data already span several values of the dipolar length and show consistent low-velocity bouncing independent of soliton sign. To strengthen the claim, the revised §5.3 will include (i) an extended parameter scan over a wider range of dipolar strengths and (ii) ensemble averages over 20–30 realizations with small random phase noise added to the initial conditions. These additions will furnish error bars on the transmission/bouncing threshold and demonstrate that the qualitative distinction from the nondipolar case persists under realistic perturbations. revision: yes

Circularity Check

0 steps flagged

No circularity: derivation from excitation spectrum is self-contained

full rationale

The abstract and available description indicate that the bound-state claim follows from computing the density and spin branches of the excitation spectrum in the binary dipolar condensate model, then identifying the spin-roton minimum as the source of periodic modulations in the inter-soliton potential. This chain rests on standard linear-response or Bogoliubov-de Gennes analysis applied to the system's Hamiltonian and dipolar interactions; no quoted step defines a quantity in terms of the target result, renames a fitted parameter as a prediction, or imports a uniqueness theorem via self-citation. The derivation remains independent of the final bound-state separations and is externally falsifiable against the underlying microscopic parameters.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The central claim rests on standard mean-field theory for dipolar BECs and the calculated excitation spectrum; no new free parameters or invented entities are introduced in the abstract.

axioms (1)
  • domain assumption The Bogoliubov-de Gennes formalism accurately captures the density and spin branches of the excitation spectrum including the roton feature.
    Standard approach invoked implicitly when stating that the rotonic feature enables the interactions.

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Works this paper leans on

65 extracted references · 65 canonical work pages

  1. [1]

    J. S. Russell,The Wave of Translation in the Oceans of Water(Trübner & Company, 1885)

  2. [2]

    Ablowitz,Nonlinear Dispersive Waves, Asymptotic Analysis and Solitons(Cambridge University Press, 2011)

    M. Ablowitz,Nonlinear Dispersive Waves, Asymptotic Analysis and Solitons(Cambridge University Press, 2011)

  3. [3]

    A. J. Heeger, S. Kivelson, J. R. Schrieffer, and W. P. Su, Solitons in conducting polymers, Rev. Mod. Phys.60, 781 (1988)

  4. [4]

    Dauxois and M

    T. Dauxois and M. Peyrard,Physics of Solitons(Cam- bridge University Press, 2006)

  5. [5]

    Y. S. Kivshar and G. P. Agrawal,Optical Solitons: From Fibers to Photonic Crystal(Academic Press, 2003)

  6. [6]

    Pitaevskii and S

    L. Pitaevskii and S. Stringari,Bose-Einstein condensa- tion and superfluidity, Vol. 164 (Oxford University Press, 2016)

  7. [7]

    P. G. Kevrekidis, D. J. Frantzeskakis, and R. Carretero- González,The defocusing nonlinear Schrödinger equa- tion: from dark solitons to vortices and vortex rings (SIAM, 2015)

  8. [8]

    Griesmaier, J

    A. Griesmaier, J. Werner, S. Hensler, J. Stuhler, and T. Pfau, Bose-einstein condensation of chromium, Phys. Rev. Lett.94, 160401 (2005)

  9. [9]

    Beaufils, R

    Q. Beaufils, R. Chicireanu, T. Zanon, B. Laburthe-Tolra, E. Maréchal, L. Vernac, J.-C. Keller, and O. Gorceix, All-opticalproductionofchromiumbose-einsteinconden- sates, Phys. Rev. A77, 061601 (2008)

  10. [10]

    M. Lu, N. Q. Burdick, S. H. Youn, and B. L. Lev, Strongly dipolar bose-einstein condensate of dysprosium, Phys. Rev. Lett.107, 190401 (2011)

  11. [11]

    Kadau, M

    H. Kadau, M. Schmitt, M. Wenzel, C. Wink, T. Maier, I. Ferrier-Barbut, and T. Pfau, Observing the rosensweig instability of a quantum ferrofluid, Nature530, 194 (2016)

  12. [12]

    Aikawa, A

    K. Aikawa, A. Frisch, M. Mark, S. Baier, A. Rietzler, R. Grimm, and F. Ferlaino, Bose-einstein condensation of erbium, Phys. Rev. Lett.108, 210401 (2012)

  13. [13]

    D. H. J. O’Dell, S. Giovanazzi, and G. Kurizki, Rotons in gaseous bose-einstein condensates irradiated by a laser, Phys. Rev. Lett.90, 110402 (2003)

  14. [14]

    Santos, G

    L. Santos, G. V. Shlyapnikov, and M. Lewenstein, Roton- maxon spectrum and stability of trapped dipolar bose- einstein condensates, Phys. Rev. Lett.90, 250403 (2003)

  15. [15]

    P. B. Blakie, D. Baillie, and R. N. Bisset, Roton spec- troscopy in a harmonically trapped dipolar bose-einstein condensate, Phys. Rev. A86, 021604 (2012)

  16. [16]

    Chomaz, R

    L. Chomaz, R. M. van Bijnen, D. Petter, G. Faraoni, S. Baier, J. H. Becher, M. J. Mark, F. Waechtler, L. San- tos, and F. Ferlaino, Observation of roton mode popula- tion in a dipolar quantum gas, Nature physics14, 442 (2018)

  17. [17]

    Petter, G

    D. Petter, G. Natale, R. M. W. van Bijnen, A. Patschei- der, M. J. Mark, L. Chomaz, and F. Ferlaino, Probing the roton excitation spectrum of a stable dipolar bose gas, Phys. Rev. Lett.122, 183401 (2019)

  18. [18]

    Schmidt, J

    J.-N. Schmidt, J. Hertkorn, M. Guo, F. Böttcher, M. Schmidt, K. S. H. Ng, S. D. Graham, T. Lan- gen, M. Zwierlein, and T. Pfau, Roton excitations in an oblate dipolar quantum gas, Phys. Rev. Lett.126, 193002 (2021)

  19. [19]

    Wächtler and L

    F. Wächtler and L. Santos, Quantum filaments in dipo- lar bose-einstein condensates, Phys. Rev. A93, 061603 (2016)

  20. [20]

    R. N. Bisset, R. M. Wilson, D. Baillie, and P. B. Blakie, Ground-state phase diagram of a dipolar condensate with quantum fluctuations, Phys. Rev. A94, 033619 (2016)

  21. [21]

    Chomaz, S

    L. Chomaz, S. Baier, D. Petter, M. Mark, F. Wächtler, L. Santos, and F. Ferlaino, Quantum-fluctuation-driven crossover from a dilute bose-einstein condensate to a macrodroplet in a dipolar quantum fluid, Physical Re- view X6, 041039 (2016)

  22. [22]

    Schmitt, M

    M. Schmitt, M. Wenzel, F. Böttcher, I. Ferrier-Barbut, and T. Pfau, Self-bound droplets of a dilute magnetic quantum liquid, Nature539, 259 (2016)

  23. [23]

    Tanzi, E

    L. Tanzi, E. Lucioni, F. Famà, J. Catani, A. Fioretti, C. Gabbanini, R. N. Bisset, L. Santos, and G. Modugno, Observation of a dipolar quantum gas with metastable supersolidproperties,Physicalreviewletters122,130405 (2019)

  24. [24]

    Böttcher, J.-N

    F. Böttcher, J.-N. Schmidt, M. Wenzel, J. Hertkorn, M. Guo, T. Langen, and T. Pfau, Transient supersolid properties in an array of dipolar quantum droplets, Phys- ical Review X9, 011051 (2019)

  25. [25]

    Chomaz, D

    L. Chomaz, D. Petter, P. Ilzhöfer, G. Natale, A. Traut- mann, C. Politi, G. Durastante, R. Van Bijnen, A. Patscheider, M. Sohmen, M. J. Mark, and F. Ferlaino, Long-lived and transient supersolid behaviors in dipolar quantum gases, Physical Review X9, 021012 (2019)

  26. [26]

    Pawłowski and K

    K. Pawłowski and K. Rzążewski, Dipolar dark solitons, New Journal of Physics17, 105006 (2015)

  27. [27]

    T.Bland, M.J.Edmonds, N.P.Proukakis, A.M.Martin, D. H. J. O’Dell, and N. G. Parker, Controllable nonlocal interactionsbetweendarksolitonsindipolarcondensates, Phys. Rev. A92, 063601 (2015)

  28. [28]

    M. A. Hoefer, J. J. Chang, C. Hamner, and P. Engels, Dark-dark solitons and modulational instability in misci- ble two-component bose-einstein condensates, Phys. Rev. A84, 041605 (2011)

  29. [29]

    D. Yan, J. Chang, C. Hamner, M. Hoefer, P. G. Kevrekidis, P. Engels, V. Achilleos, D. J. Frantzeskakis, and J. Cuevas, Beating dark–dark solitons in bose– einstein condensates, Journal of Physics B: Atomic, Molecular and Optical Physics45, 115301 (2012)

  30. [30]

    Danaila, M

    I. Danaila, M. A.Khamehchi, V.Gokhroo, P.Engels,and P. G. Kevrekidis, Vector dark-antidark solitary waves in multicomponent bose-einstein condensates, Phys. Rev. A 94, 053617 (2016)

  31. [31]

    Farolfi, D

    A. Farolfi, D. Trypogeorgos, C. Mordini, G. Lamporesi, and G. Ferrari, Observation of magnetic solitons in two- component bose-einstein condensates, Phys. Rev. Lett. 125, 030401 (2020)

  32. [32]

    X. Chai, D. Lao, K. Fujimoto, R. Hamazaki, M. Ueda, and C. Raman, Magnetic solitons in a spin-1 bose- einsteincondensate,Phys.Rev.Lett.125,030402(2020)

  33. [33]

    G. C. Katsimiga, S. I. Mistakidis, T. M. Bersano, 7 M. K. H. Ome, S. M. Mossman, K. Mukherjee, P. Schmelcher, P. Engels, and P. G. Kevrekidis, Obser- vation and analysis of multiple dark-antidark solitons in two-component bose-einstein condensates, Phys. Rev. A 102, 023301 (2020)

  34. [34]

    S. M. Mossman, G. C. Katsimiga, S. I. Mistakidis, A. Romero-Ros, T. M. Bersano, P. Schmelcher, P. G. Kevrekidis, and P. Engels, Observation of dense col- lisional soliton complexes in a two-component bose- einstein condensate, Communications Physics7, 163 (2024)

  35. [35]

    Öhberg and L

    P. Öhberg and L. Santos, Dark solitons in a two- component bose-einstein condensate, Phys. Rev. Lett. 86, 2918 (2001)

  36. [36]

    E. G. Charalampidis, W. Wang, P. G. Kevrekidis, D. J. Frantzeskakis, and J. Cuevas-Maraver, SO(2)-induced breathing patterns in multicomponent bose-einstein con- densates, Phys. Rev. A93, 063623 (2016)

  37. [37]

    Wang, L.-C

    W. Wang, L.-C. Zhao, E. G. Charalampidis, and P. G. Kevrekidis, Dark–dark soliton breathing patterns in multi-component bose–einstein condensates, Journal of Physics B: Atomic, Molecular and Optical Physics54, 055301 (2021)

  38. [38]

    Röhrs, C

    R. Röhrs, C. Qu, and R. Bisset, Magnetic soli- ton molecules in binary condensates, arXiv preprint arXiv:2508.21778 (2025)

  39. [39]

    Trautmann, P

    A. Trautmann, P. Ilzhöfer, G. Durastante, C. Politi, M. Sohmen, M. J. Mark, and F. Ferlaino, Dipolar quan- tum mixtures of erbium and dysprosium atoms, Phys. Rev. Lett.121, 213601 (2018)

  40. [40]

    Ravensbergen, E

    C. Ravensbergen, E. Soave, V. Corre, M. Kreyer, B. Huang, E. Kirilov, and R. Grimm, Resonantly inter- acting fermi-fermi mixture of161Dyand 40K, Phys. Rev. Lett.124, 203402 (2020)

  41. [41]

    Durastante, C

    G. Durastante, C. Politi, M. Sohmen, P. Ilzhöfer, M. J. Mark, M. A. Norcia, and F. Ferlaino, Feshbach reso- nances in an erbium-dysprosium dipolar mixture, Phys. Rev. A102, 033330 (2020)

  42. [42]

    Politi, A

    C. Politi, A. Trautmann, P. Ilzhöfer, G. Durastante, M. Mark, M. Modugno, and F. Ferlaino, Interspecies in- teractions in an ultracold dipolar mixture, Physical Re- view A105, 023304 (2022)

  43. [43]

    Schäfer, Y

    F. Schäfer, Y. Haruna, and Y. Takahashi, Realization of a quantum degenerate mixture of highly magnetic and nonmagnetic atoms, Phys. Rev. A107, L031306 (2023)

  44. [44]

    Lecomte, A

    M. Lecomte, A. Journeaux, J. Veschambre, J. Dalibard, and R. Lopes, Production and stabilization of a spin mix- ture of ultracold dipolar bose gases, Physical Review Let- ters134, 013402 (2025)

  45. [45]

    Kalia, J

    J. Kalia, J. Rivera, R. R. Emran, W. J. S. Hernandez, K. Kwon, and R. J. Fletcher, Creation of a degenerate bose-bose mixture of erbium and lithium atoms, arXiv preprint arXiv:2506.00177 (2025)

  46. [46]

    Giovanazzi and D

    S. Giovanazzi and D. H. O’Dell, Instabilities and the roton spectrum of a quasi-1d bose-einstein condensed gas with dipole-dipole interactions, The European Phys- ical Journal D-Atomic, Molecular, Optical and Plasma Physics31, 439 (2004)

  47. [47]

    Sinha and L

    S. Sinha and L. Santos, Cold dipolar gases in quasi- one-dimensional geometries, Physical review letters99, 140406 (2007)

  48. [48]

    S. Pal, D. Baillie, and P. Blakie, Excitations and number fluctuations in an elongated dipolar bose-einstein con- densate, Physical Review A102, 043306 (2020)

  49. [49]

    R. M. Wilson, C. Ticknor, J. L. Bohn, and E. Timmer- mans, Roton immiscibility in a two-component dipolar bose gas, Physical Review A86, 033606 (2012)

  50. [50]

    A.-C. Lee, D. Baillie, P. Blakie, and R. Bisset, Misci- bility and stability of dipolar bosonic mixtures, Physical Review A103, 063301 (2021)

  51. [51]

    Kirkby, T

    W. Kirkby, T. Bland, F. Ferlaino, and R. N. Bisset, Spin rotons and supersolids in binary antidipolar condensates, SciPost Physics Core6, 084 (2023)

  52. [52]

    H.-Y. Lu, H. Lu, J.-N. Zhang, R.-Z. Qiu, H. Pu, and S. Yi, Spatial density oscillations in trapped dipolar con- densates, Physical Review A82, 023622 (2010)

  53. [53]

    Yi and H

    S. Yi and H. Pu, Vortex structures in dipolar conden- sates, Physical Review A73, 061602 (2006)

  54. [54]

    R. M. Wilson, S. Ronen, J. L. Bohn, and H. Pu, Mani- festations of the roton mode in dipolar bose-einstein con- densates, Physical review letters100, 245302 (2008)

  55. [55]

    Ronen, D

    S. Ronen, D. C. Bortolotti, and J. L. Bohn, Radial and angular rotons in trapped dipolar gases, Physical review letters98, 030406 (2007)

  56. [56]

    Regge, Free boundary of he ii and feynman wave func- tions, Journal of Low Temperature Physics9, 123 (1972)

    T. Regge, Free boundary of he ii and feynman wave func- tions, Journal of Low Temperature Physics9, 123 (1972)

  57. [57]

    Dalfovo, Structure of vortices in helium at zero tem- perature, Physical Review B46, 5482 (1992)

    F. Dalfovo, Structure of vortices in helium at zero tem- perature, Physical Review B46, 5482 (1992)

  58. [58]

    W. E. Shirley, B. M. Anderson, C. W. Clark, and R. M. Wilson, Half-quantum vortex molecules in a binary dipo- lar bose gas, Physical Review Letters113, 165301 (2014)

  59. [59]

    Kirkby, A.-C

    W. Kirkby, A.-C. Lee, D. Baillie, T. Bland, F. Ferlaino, P. Blakie, and R. Bisset, Excitations of a binary dipolar supersolid, Physical review letters133, 103401 (2024)

  60. [60]

    As a result, the critical value ofa12 is approxi- mately 1% higher in Figs

    Note that while the dispersion relation is calculated for the homogeneous system, the numerical simulations in- troduce a small finite-size effect due to the presence of the soliton. As a result, the critical value ofa12 is approxi- mately 1% higher in Figs. 2(a2,b2) that in Figs. 2(a1,b1)

  61. [61]

    C. Qu, L. P. Pitaevskii, and S. Stringari, Magnetic soli- tons in a binary bose-einstein condensate, Phys. Rev. Lett.116, 160402 (2016)

  62. [62]

    Bland, E

    T. Bland, E. Poli, L. P. Ardila, L. Santos, F. Ferlaino, and R. N. Bisset, Alternating-domain supersolids in bi- narydipolarcondensates,PhysicalReviewA106,053322 (2022)

  63. [63]

    S. Li, U. N. Le, and H. Saito, Long-lifetime supersolid in a two-component dipolar bose-einstein condensate, Phys- ical Review A105, L061302 (2022)

  64. [64]

    Bland, K

    T. Bland, K. Pawłowski, M. Edmonds, K. Rzążewski, and N. Parker, Interaction-sensitive oscillations of dark solitons in trapped dipolar condensates, Physical Review A95, 063622 (2017)

  65. [65]

    3, the highest value ofa12 considered is at least 1a0 below this threshold

    In Fig. 3, the highest value ofa12 considered is at least 1a0 below this threshold. Appendix A: Bogoliubov theory This derivation of the dispersion relations for elemen- tary excitations is similar to the one in Ref. [51] for an- tidipolar mixtures. We look for solutions of Eq. (3) of the form: ψi(x, t) = √ni +λ h ui(x)e−iϵt/ℏ −v ∗ i (x)eiϵ∗t/ℏ i e−iµit/ℏ...