Kelvin Modes of a fast rotating Bose-Einstein Condensate

TL;DR

This paper investigates the eigenmodes of a rapidly rotating Bose-Einstein condensate with vortices, predicting a new branch of excitations similar to Kelvin modes and analyzing the anomalous scissors mode.

Contribution

It introduces a formalism for calculating eigenmodes in vortex-laden condensates and predicts novel Kelvin-like excitation modes.

Findings

Identification of a new branch of anomalous excitations

Prediction of Kelvin mode analogs in condensates

Analysis of the anomalous scissors mode excitation

Abstract

Using the concept of diffused vorticity and the formalism of rotational hydrodynamics we calculate the eigenmodes of a harmonically trapped Bose-Einstein condensate containing an array of quantized vortices. We predict the occurrence of a new branch of anomalous excitations, analogous to the Kelvin modes of the single vortex dynamics. Special attention is devoted to the excitation of the anomalous scissors mode.