Repulsive bound-atom pairs in an optical lattice with two-body interaction of nearest neighbors

Journal Article · Thu Apr 15 00:00:00 EDT 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.81.045601· OSTI ID:21413349

Wang, Y -M; Liang, J -Q ^[1]

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1. Department of Physics, Institute of Theoretical Physics, Shanxi University, Taiyuan 030006 (China)

Repulsively interacting particles in a periodic potential can form bound composite objects with long lifetimes, as has been observed experimentally [Winkler et al., Nature (London) 441, 853 (2006)]. In this paper, a complete two-particle solution of one-dimensional periodical potential was derived in a strong interaction regime, where the on-site approximation of a two-body interaction in the Bose-Hubbard model (BHM) is extended to include the interaction of nearest neighbors, which results in atom-pair hopping. The energy spectrum of the bound pair is drastically reshaped due to the pair-hopping term, and complex eigenenergy corresponding to metastable states is also found that has not been discovered in the usual BHM. When the absolute value of a center-of-mass quasimomentum wave vector is greater than a critical value (|K|>K{sub c}), two bound-pair solutions are found. Furthermore, the spatial and momentum distributions of the bound pair displays a crossover from dark to bright soliton-like solutions in the extended BHM. Our results reduce to that of the usual BHM in the weak interaction case.

• OSTI ID: 21413349
• Journal Information: Physical Review. A, Vol. 81, Issue 4; Other Information: DOI: 10.1103/PhysRevA.81.045601; (c) 2010 The American Physical Society; ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
74 ATOMIC AND MOLECULAR PHYSICS
APPROXIMATIONS
ATOMS
ENERGY SPECTRA
HUBBARD MODEL
INTERACTIONS
MATHEMATICAL SOLUTIONS
METASTABLE STATES
ONE-DIMENSIONAL CALCULATIONS
PERIODICITY
POTENTIALS
SOLITONS
TWO-BODY PROBLEM
VECTORS
CALCULATION METHODS
CRYSTAL MODELS
ENERGY LEVELS
EXCITED STATES
MANY-BODY PROBLEM
MATHEMATICAL MODELS
QUASI PARTICLES
SPECTRA
TENSORS
VARIATIONS