Dynamics of Bose-Einstein Condensates in One-Dimensional Optical Lattices in the Presence of Transverse Resonances

TL;DR

This paper develops an effective one-dimensional model for Bose-Einstein condensates in optical lattices that incorporates transverse resonances, leading to new insights into their complex dynamics and the proposal of a novel 'triple soliton' state.

Contribution

It introduces a variational theory accounting for transverse resonances in 1D optical lattices and proposes a new 'triple soliton' configuration.

Findings

Effective 1D theory incorporating transverse modes

Derivation of variational equations for large-scale dynamics

Proposal of a novel 'triple soliton' state

Abstract

The dynamics of Bose-Einstein condensates in the lowest energy band of a one-dimensional optical lattice is generally disturbed by the presence of transversally excited resonant states. We propose an effective one-dimensional theory which takes these resonant modes into account and derive variational equations for large-scale dynamics. Several applications of the theory are discussed and a novel type of "triple soliton" is proposed, which consists of a superposition of a wavepacket at the upper band edge and two transversally excited wavepackets which are displaced in quasi-momentum space.