Surface modes and vortex formation in dilute Bose-Einstein condensates at finite temperatures

TL;DR

This paper investigates how surface excitations in dilute Bose-Einstein condensates influence vortex formation at finite temperatures, revealing temperature-dependent critical frequencies that align with experimental data.

Contribution

It provides a self-consistent calculation of surface mode spectra at finite temperatures, linking surface excitations to vortex nucleation and stability.

Findings

Critical vortex nucleation frequency increases with temperature.

Surface excitation multipolarity decreases as temperature rises.

Finite-temperature critical frequencies agree with experiments and zero-temperature theory.

Abstract

The surface mode spectrum is computed self-consistently for dilute Bose-Einstein condensates, providing the temperature dependence of the surface mode induced vortex nucleation frequency. Both the thermodynamic critical frequency for vortex stability and the nucleation frequency implied by the surface excitations increase as the critical condensation temperature is approached from below. The multipolarity of the destabilizing surface excitation decreases with increasing temperature. The computed finite-temperature critical frequencies support the experimental observations and the zero-temperature calculations for vortex nucleation.