Particle-Imbalanced Bose Mixtures in the Droplet Regime

We unravel the transition of the bound state behavior of attractively interacting two-component bosonic mixtures from particle balanced settings towards the impurity limit. A multitude of phases is found to occur depending on the interplay between the intercomponent attraction and the particle-imbalance. For weak attractions (droplet regime) and larger imbalances the flat-top density profile of the majority component becomes progressively localized and it is restricted within the spatial region where the minority one is located. In contrast, turning to stronger attractions, the highly localized soliton-like state of the majority species features a spatial delocalization and eventually exhibits a flattened background for sufficiently large particle imbalance. A depletion of the density profile accompanied by strong two-body correlations is evinced for increasing repulsion of the minority component. The aforementioned structural deformations are explained by constructing a suitable effective potential approach within the modified Gross-Pitaevskii model, while the few- to many-body crossover is probed through an ab-initio variational approach.