A Variational Sum-Rule Approach to Collective Excitations of a Trapped Bose-Einstein Condensate

TL;DR

This paper introduces a variational sum-rule method combined with Fetter's trial wave function to accurately compute low-lying collective excitation frequencies of a trapped Bose-Einstein condensate at zero temperature.

Contribution

The paper presents a novel variational sum-rule approach that yields nearly exact collective-mode frequencies for trapped Bose-Einstein condensates, improving theoretical predictions.

Findings

Accurate calculation of low-lying collective-mode frequencies

Method matches experimental and numerical results closely

Effective for zero-temperature BEC excitations

Abstract

It is found that combining an excitation-energy sum rule with Fetter's trial wave function gives almost exact low-lying collective-mode frequencies of a trapped Bose-Einstein condensate at zero temperature.