A dipolar droplet bound in a trapped Bose-Einstein condensate

TL;DR

This paper investigates the stability, shape, and dynamics of a dipolar 164Dy BEC droplet bound within a trapped non-dipolar 87Rb BEC, using numerical and variational methods, and proposes an experimental realization method.

Contribution

It provides the first detailed analysis of a dipolar Dy droplet bound in a non-dipolar BEC, including stability conditions and dynamic behavior, with an experimental proposal.

Findings

Stable dipolar Dy droplets exist within specific atom number and scattering length ranges.

Shape and size of the droplet depend on inter-species interactions and atom number.

Breathing oscillations of the droplet are characterized and modeled.

Abstract

We study the statics and dynamics of a dipolar Bose-Einstein condensate (BEC) droplet bound by inter-species contact interaction in a trapped non-dipolar BEC. Our findings are demonstrated in terms of stability plots of a dipolar 164Dy droplet bound in a trapped non-dipolar 87Rb BEC with a variable number of 164Dy atoms and the inter-species scattering length. A trapped non-dipolar BEC of a fixed number of atoms can only bind a dipolar droplet containing atoms less than a critical number for the inter-species scattering length between two critical values. The shape and size (statics) as well as the small breathing oscillation (dynamics) of the dipolar BEC droplet are studied using the numerical and variational solutions of a mean-field model. We also suggest an experimental procedure for achieving such a 164Dy droplet by relaxing the trap on the 164Dy BEC in a trapped binary 87Rb-164Dy mixture.