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Few-body bound states of two-dimensional bosons Guijarro Gámez, Grecia Astrakharchik, Grigori Boronat Medico, Jordi Bazak, Betzalel Petrov, D. S. Universitat Politècnica de Catalunya. Departament de Física Universitat Politècnica de Catalunya. SIMCON - First-principles approaches to condensed matter physics: quantum effects and complexity Àrees temàtiques de la UPC::Física Bosons Bosons Bound states Few-body systems Bosons We study clusters of the type $A_NB_M$ with N=M=3 in a two-dimensional mixture of A and B bosons, with attractive AB and equally repulsive AA and BB interactions. In order to check universal aspects of the problem, we choose two very different models: dipolar bosons in a bilayer geometry and particles interacting via separable Gaussian potentials. We find that all the considered clusters are bound and that their energies are universal functions of the scattering lengths $a_{AB}$ and $a{AA}=a_{BB}$, for sufficiently large attraction-to-repulsion ratios $a_{AB}/a_{BB}$. When $a_{AB}/a_{BB}$ decreases below ˜10, the dimer-dimer interaction changes from attractive to repulsive and the population-balanced AABB and AAABBB clusters break into AB dimers. Calculating the AAABBB hexamer energy just below this threshold, we find an effective three-dimer repulsion which may have important implications for the many-body problem, particularly for observing liquid and supersolid states of dipolar dimers in the bilayer geometry. The population-imbalanced ABB trimer, ABBB tetramer, and AABBB pentamer remain bound beyond the dimer-dimer threshold. In the dipolar model, they break up at $a_{AB}˜2a_{BB}, where the atom-dimer interaction switches to repulsion. Postprint (published version) 2020-04-07 Article Guijarro, G. [et al.]. Few-body bound states of two-dimensional bosons. "Physical review A", 7 Abril 2020, vol. 101, núm. 4, p. 041602:1-041602:6. 2469-9926 https://hdl.handle.net/2117/330657 10.1103/PhysRevA.101.041602 eng https://journals.aps.org/pra/abstract/10.1103/PhysRevA.101.041602 http://creativecommons.org/licenses/by-nc-nd/3.0/es/ Open Access Attribution-NonCommercial-NoDerivs 3.0 Spain application/pdf American Physical Society (APS)