Controlling Grey Solitons in a Trap

TL;DR

This paper analytically studies grey solitons in a trapped Bose-Einstein condensate, revealing their strong coupling with the trap and potential for control via trap and interaction modulation.

Contribution

It provides an analytical extraction of grey solitons from the Gross-Pitaevskii equation and explores their coupling with trap modes for the first time.

Findings

Grey solitons strongly couple with trap at low momenta.

They can be isolated from Bogoliubov sound modes.

Grey solitons are controllable through trap and interaction modulation.

Abstract

Experimentally observed grey solitons are analytically extracted from a physically viable \GP equation. Associated Lieb and Bogoliubov modes are calculated for these class of solitons. It is observed that, these nonlinear excitations have strong coupling with the trap at low momenta and hence can be effectively isolated from the Bogoliubov sound modes, which responds weakly to harmonic confinement. This strong coupling with the trap also makes the grey soliton amenable for control and manipulation through both trap modulation and temporal variation of the two-body interaction.