Phenomenological description of the vortex density in rotating BEC superfluids

TL;DR

This paper introduces a phenomenological model describing how vortex density in rotating Bose-Einstein condensates varies with angular speed, bridging understanding with superfluid helium.

Contribution

It presents a new phenomenological equation for vortex line density in rotating BECs, capturing the transition from initial vortex appearance to rigid-body rotation.

Findings

The equation describes the increase in vortex number with angular speed.

It allows comparison between BECs and superfluid helium.

The model aligns with theoretical expectations for high vortex densities.

Abstract

We propose a phenomenological equation for the vortex line density in rotating Bose-Einstein condensates as a function of the angular speed. This equation provides a simple description of the gross features of the increase in vortex number from the appearance of the first vortex to the theoretical rigid-body result for high vortex density, and allows one to compare with analogous situations in superfluid helium, after the suitable changes in the relevant parameters are made.