Localization of a Bose-Einstein condensate vortex in a bichromatic optical lattice

TL;DR

This paper demonstrates that a Bose-Einstein condensate vortex can be localized in a three-dimensional bichromatic optical lattice, extending previous one-dimensional results, and confirms the stability of this localized state through numerical simulations.

Contribution

It generalizes BEC localization from 1D to 3D bichromatic optical lattices and analyzes the stability of the localized vortex state over time.

Findings

Localization of BEC vortex in 3D bichromatic OL demonstrated

Localized state remains stable with breathing oscillations

Extension of localization concept to random 1D potentials

Abstract

By numerical simulation of the time-dependent Gross-Pitaevskii equation we show that a weakly interacting or noninteracting Bose-Einstein condensate (BEC) vortex can be localized in a three-dimensional bichromatic quasi-periodic optical-lattice (OL) potential generated by the superposition of two standing-wave polarized laser beams with incommensurate wavelengths. This is a generalization of the localization of a BEC in a one-dimensional bichromatic OL as studied in a recent experiment [Roati et al., Nature 453, 895 (2008)]. We demonstrate the stability of the localized state by considering its time evolution in the form of a stable breathing oscillation in a slightly altered potential for a large period of time. {Finally, we consider the localization of a BEC in a random 1D potential in the form of several identical repulsive spikes arbitrarily distributed in space.