Spatially-antisymmetric localization of matter wave in a bichromatic optical lattice

TL;DR

This paper investigates the double-humped, spatially-antisymmetric localization of a Bose-Einstein condensate in a one-dimensional bichromatic optical lattice, using numerical simulations and variational analysis to explore stability and properties.

Contribution

It presents a detailed numerical study of antisymmetric localized states in a bichromatic optical lattice, including stability analysis and comparison with variational methods.

Findings

Confirmed the existence of stable double-humped localized states.

Compared numerical results with variational analysis for accuracy.

Demonstrated stability of localized states under small perturbations.

Abstract

By direct numerical simulation of the time-dependent Gross-Pitaevskii equation using the split-step Fourier spectral method we study the double-humped localization of a cigar-shaped Bose-Einstein condensate (BEC) in a one-dimensional bichromatic quasi-periodic optical-lattice potential, as used in a recent experiment on the localization of a BEC [Roati et al., Nature 453, 895 (2008)]. Such states are spatially antisymmetric and are excited modes of Anderson localization. Where possible, we have compared the numerical results with a variational analysis. We also demonstrate the stability of the localized double-humped BEC states under small perturbation.