Dynamics in asymmetric double-well condensates

TL;DR

This paper develops a two-mode model to analyze the dynamics of Bose-Einstein condensates in asymmetric double-well traps, incorporating interaction corrections and validating results against Gross-Pitaevskii simulations.

Contribution

It introduces an improved two-mode formalism for asymmetric double-well condensates, including interaction effects and phase-space analysis, validated with experimental and numerical data.

Findings

Phase-space minimum shifts due to asymmetry.

Good agreement between model and Gross-Pitaevskii simulations.

Enhanced model accuracy for trap asymmetries.

Abstract

The dynamics of Bose-Einstein condensates in asymmetric double-wells is studied. We construct a two-mode model and analyze the properties of the corresponding phase-space diagram, showing in particular that the minimum of the phase-space portrait becomes shifted from the origin as a consequence of the nonvanishing overlap between the ground and excited states from which the localized states are derived. We further incorporate effective interaction corrections in the set of two-mode model parameters. Such a formalism is applied to a recent experimentally explored system, which is confined by a toroidal trap with radial barriers forming an arbitrary angle between them. We confront the model results with Gross-Pitaevskii simulations for various angle values finding a very good agreement. We also analyze the accuracy of a previously employed simple model for moving barriers, exploring a possible improvement that could cover a wider range of trap asymmetries.