Spin textures in rotating two-component Bose-Einstein condensates

Journal Article · Fri Apr 01 00:00:00 EST 2005 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.71.043611· OSTI ID:20653335

Kasamatsu, Kenichi; Tsubota, Makoto; Ueda, Masahito ^[1]

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1. Department of General Education, Ishikawa National College of Technology, Tsubata, Ishikawa 929-0392 (Japan)

We investigate two kinds of coreless vortices with axisymmetric and nonaxisymmetric configurations in rotating two-component Bose-Einstein condensates. Starting from the Gross-Pitaevskii energy functional in a rotating frame, we derive a nonlinear sigma model generalized to the two-component condensates. In terms of a pseudospin representation, an axisymmetric vortex and a nonaxisymmetric one correspond to spin textures referred to as a 'skyrmion' and a 'meron-pair', respectively. A variational method is used to investigate the dependence of the sizes of the stable spin textures on system parameters, and the optimized variational function is found to reproduce well the numerical solution. In the SU(2) symmetric case, the optimal skyrmion and meron-pair are degenerate and transform to each other by a rotation of the pseudospin. An external rf field that couples coherently the hyperfine states of two components breaks the degeneracy in favor of the meron-pair texture due to an effective transverse pseudomagnetic field. The difference between the intracomponent and intercomponent interactions yields a longitudinal pseudomagnetic field and a ferromagnetic or an antiferromagnetic pseudospin interaction, leading to a meron-pair texture with an anisotropic distribution of vorticity.

• OSTI ID: 20653335
• Journal Information: Physical Review. A, Vol. 71, Issue 4; Other Information: DOI: 10.1103/PhysRevA.71.043611; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ANISOTROPY
ANTIFERROMAGNETISM
AXIAL SYMMETRY
BOSE-EINSTEIN CONDENSATION
DISTRIBUTION
FERROMAGNETISM
NONLINEAR PROBLEMS
NUMERICAL SOLUTION
OPTIMIZATION
ROTATION
SIGMA MODEL
SKYRME POTENTIAL
SOLITONS
SPIN
SU-2 GROUPS
TEXTURE
VARIATIONAL METHODS
VORTICES
WAVE EQUATIONS
YIELDS