# Multicomponent gap solitons in spinor Bose-Einstein condensates

## Abstract

We model the nonlinear behavior of spin-1 Bose-Einstein condensates (BECs) with repulsive spin-independent interactions and either ferromagnetic or antiferromagnetic (polar) spin-dependent interactions, loaded into a one-dimensional 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 self-trapped waves that exist only within gaps of the linear Bloch-wave band-gap 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 mean-field treatment. We show that the non-SMA states can exhibits Josephson-like internal oscillations and self-magnetization, i.e., intrinsic precession of the local spin. Finally, we demonstrate that nonstationary states of a spinor BEC in a lattice exhibit coherent undamped spin-mixing 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 Quantum-Atom 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; BOSE-EINSTEIN CONDENSATION; CONDENSATES; DENSITY; INSTABILITY; INTERACTIONS; JOSEPHSON EFFECT; MAGNETIC FIELDS; MAGNETIZATION; MEAN-FIELD THEORY; MIXING; NONLINEAR PROBLEMS; ONE-DIMENSIONAL CALCULATIONS; OPTICAL MODELS; OSCILLATIONS; POTENTIALS; SOLITONS; SPIN; TRAPPING

### Citation Formats

```
DaPbrowska-Wuester, Beata J., Ostrovskaya, Elena A., Alexander, Tristram J., and Kivshar, Yuri S.
```*Multicomponent gap solitons in spinor Bose-Einstein condensates*. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVA.75.023617.

```
DaPbrowska-Wuester, Beata J., Ostrovskaya, Elena A., Alexander, Tristram J., & Kivshar, Yuri S.
```*Multicomponent gap solitons in spinor Bose-Einstein condensates*. United States. doi:10.1103/PHYSREVA.75.023617.

```
DaPbrowska-Wuester, Beata J., Ostrovskaya, Elena A., Alexander, Tristram J., and Kivshar, Yuri S. Thu .
"Multicomponent gap solitons in spinor Bose-Einstein condensates". United States.
doi:10.1103/PHYSREVA.75.023617.
```

```
@article{osti_20982168,
```

title = {Multicomponent gap solitons in spinor Bose-Einstein condensates},

author = {DaPbrowska-Wuester, Beata J. and Ostrovskaya, Elena A. and Alexander, Tristram J. and Kivshar, Yuri S.},

abstractNote = {We model the nonlinear behavior of spin-1 Bose-Einstein condensates (BECs) with repulsive spin-independent interactions and either ferromagnetic or antiferromagnetic (polar) spin-dependent interactions, loaded into a one-dimensional 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 self-trapped waves that exist only within gaps of the linear Bloch-wave band-gap 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 mean-field treatment. We show that the non-SMA states can exhibits Josephson-like internal oscillations and self-magnetization, i.e., intrinsic precession of the local spin. Finally, we demonstrate that nonstationary states of a spinor BEC in a lattice exhibit coherent undamped spin-mixing 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}

}