Capillary Flotation in a System of Two Immiscible Bose-Einstein Condensates

TL;DR

This paper demonstrates through numerical simulation that surface tension in phase-separated two-component Bose-Einstein condensates allows for stable floating drops of one phase on another, influenced by trap anisotropy and system parameters.

Contribution

First numerical demonstration of stable floating drops in phase-separated Bose-Einstein condensates due to surface tension effects.

Findings

Stable equilibrium positions depend on trap anisotropy.

Drops can float with attached quantized vortices.

Surface tension enables new phase separation phenomena.

Abstract

A spatially inhomogeneous, trapped two-component Bose-Einstein condensate of cold atoms in the phase separation mode has been numerically simulated. It has been demonstrated for the first time that the surface tension between the components makes possible the existence of drops of a denser phase floating on the surface of a less dense phase. Depending on the harmonic trap anisotropy and other system parameters, a stable equilibrium of the drop is achieved either at the poles or at the equator. The drop flotation sometimes persists even in the presence of an attached quantized vortex.