Multicomponent gap solitons in spinor BoseEinstein condensates
Abstract
We model the nonlinear behavior of spin1 BoseEinstein condensates (BECs) with repulsive spinindependent interactions and either ferromagnetic or antiferromagnetic (polar) spindependent interactions, loaded into a onedimensional optical lattice potential. We show that both types of BECs exhibit dynamical instabilities and may form spatially localized multicomponent structures. The localized states of the spinor matter waves take the form of vector gap solitons and selftrapped waves that exist only within gaps of the linear Blochwave bandgap spectrum. Of special interest are the nonlinear localized states that do not exhibit a common spatial density profile shared by all condensate components, and consequently cannot be described by the single mode approximation (SMA) frequently employed within the framework of the meanfield treatment. We show that the nonSMA states can exhibits Josephsonlike internal oscillations and selfmagnetization, i.e., intrinsic precession of the local spin. Finally, we demonstrate that nonstationary states of a spinor BEC in a lattice exhibit coherent undamped spinmixing dynamics, and that their controlled conversion into a stationary state can be achieved by the application of an external magnetic field.
 Authors:
 ARC Centre of Excellence for QuantumAtom Optics and Nonlinear Physics Centre, Research School of Physical Sciences and Engineering, The Australian National University, Canberra ACT 0200 (Australia)
 Publication Date:
 OSTI Identifier:
 20982168
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.75.023617; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANTIFERROMAGNETISM; APPROXIMATIONS; BOSEEINSTEIN CONDENSATION; CONDENSATES; DENSITY; INSTABILITY; INTERACTIONS; JOSEPHSON EFFECT; MAGNETIC FIELDS; MAGNETIZATION; MEANFIELD THEORY; MIXING; NONLINEAR PROBLEMS; ONEDIMENSIONAL CALCULATIONS; OPTICAL MODELS; OSCILLATIONS; POTENTIALS; SOLITONS; SPIN; TRAPPING
Citation Formats
DaPbrowskaWuester, Beata J., Ostrovskaya, Elena A., Alexander, Tristram J., and Kivshar, Yuri S.. Multicomponent gap solitons in spinor BoseEinstein condensates. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVA.75.023617.
DaPbrowskaWuester, Beata J., Ostrovskaya, Elena A., Alexander, Tristram J., & Kivshar, Yuri S.. Multicomponent gap solitons in spinor BoseEinstein condensates. United States. doi:10.1103/PHYSREVA.75.023617.
DaPbrowskaWuester, Beata J., Ostrovskaya, Elena A., Alexander, Tristram J., and Kivshar, Yuri S.. Thu .
"Multicomponent gap solitons in spinor BoseEinstein condensates". United States.
doi:10.1103/PHYSREVA.75.023617.
@article{osti_20982168,
title = {Multicomponent gap solitons in spinor BoseEinstein condensates},
author = {DaPbrowskaWuester, Beata J. and Ostrovskaya, Elena A. and Alexander, Tristram J. and Kivshar, Yuri S.},
abstractNote = {We model the nonlinear behavior of spin1 BoseEinstein condensates (BECs) with repulsive spinindependent interactions and either ferromagnetic or antiferromagnetic (polar) spindependent interactions, loaded into a onedimensional optical lattice potential. We show that both types of BECs exhibit dynamical instabilities and may form spatially localized multicomponent structures. The localized states of the spinor matter waves take the form of vector gap solitons and selftrapped waves that exist only within gaps of the linear Blochwave bandgap spectrum. Of special interest are the nonlinear localized states that do not exhibit a common spatial density profile shared by all condensate components, and consequently cannot be described by the single mode approximation (SMA) frequently employed within the framework of the meanfield treatment. We show that the nonSMA states can exhibits Josephsonlike internal oscillations and selfmagnetization, i.e., intrinsic precession of the local spin. Finally, we demonstrate that nonstationary states of a spinor BEC in a lattice exhibit coherent undamped spinmixing dynamics, and that their controlled conversion into a stationary state can be achieved by the application of an external magnetic field.},
doi = {10.1103/PHYSREVA.75.023617},
journal = {Physical Review. A},
number = 2,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}

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