Band-gap structure and chiral discrete solitons in optical lattices with artificial gauge fields

TL;DR

This paper investigates the band-gap structure and chiral discrete solitons in three-leg-ladder optical lattices with artificial gauge fields, revealing exotic energy structures and stable edge-associated solitons in Bose-Einstein condensates.

Contribution

It introduces the analysis of band-gap structures and the discovery of stable chiral discrete solitons in optical lattices with artificial gauge fields, highlighting their unique properties.

Findings

Exotic swallow-tail loop structures in energy spectra.

Stable discrete solitons linked to chiral edge currents.

Interaction and gauge fields influence energy-level anti-crossings.

Abstract

We study three-leg-ladder optical lattices loaded with repulsive atomic Bose-Einstein condensates and subjected to artificial gauge fields. By employing the plane-wave analysis and variational approach, we analyze the band-gap structure of the energy spectrum and reveal the exotic swallow-tail loop structures in the energy-level anti-crossing regions due to an interplay between the atom-atom interaction and artificial gauge field. Also, we discover stable discrete solitons residing in a semi-infinite gap above the highest band, these discrete solitons are associated with the chiral edge currents.