Phases and dynamics of an impurity immersed in one-dimensional quantum droplets

TL;DR

This paper investigates how a single impurity interacts with a one-dimensional quantum droplet, revealing controllable density profiles, phase separation, and the importance of correlations through ab-initio simulations and comparisons with mean-field models.

Contribution

It demonstrates the controllable shaping of impurity-affected droplet profiles and highlights the role of correlations in impurity-droplet interactions using ab-initio methods.

Findings

Impurity localization occurs with attractive interactions, causing a density hump.

Repulsive interactions lead to phase separation between impurity and droplet.

Mean-field models overestimate impurity localization compared to many-body results.

Abstract

We explore the ground-state properties of a single impurity immersed in a one-dimensional quantum droplet medium formed by a two-component Bose mixture. Relying on ab-initio simulations, we demonstrate that tuning the impurity-droplet interactions allows to controllably reshape the droplets density profiles and associated correlation patterns. For attractive impurity-medium couplings, the impurity becomes localized within the droplet which exhibits a density hump at the vicinity of the impurity, while repulsive interactions facilitate their phase-separation. Comparing our many-body results to the appropriate extended Gross-Pitaevskii description, we find adequate agreement for the droplet density profiles, with the effective field approach systematically overestimating impurity localization. Following a release of the external trap, we unveil that the sign and magnitude of the interactions between the impurity and the droplet hosts dictate the response of the three-component setting which experiences expansion unless strongly attractive intercomponent couplings are present. These results corroborate the role and presence of correlations in impurity-droplet mixtures and inspire future investigations on impurity physics for probing droplet configurations.