Partially incoherent gap solitons in Bose-Einstein condensates

Journal Article · Fri Sep 15 04:00:00 EDT 2006 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.74.033614· OSTI ID:20857742

Merhasin, I M ^[1]; Malomed, Boris A ^[2]; Band, Y B ^[3]

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1. Department of Electrical and Electronics Engineering, College of Judea and Samaria, Ariel (Israel)
2. Department of Interdisciplinary Studies, School of Electrical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978 (Israel)
3. Departments of Chemistry and Electro-Optics, and Ilse Katz Center for Nano-Science, Ben-Gurion University, Beer Sheva 84105 (Israel)

We construct families of incoherent matter-wave solitons in a repulsive degenerate Bose gas trapped in an optical lattice (OL), i.e., gap solitons, and investigate their stability at zero and finite temperature, using the Hartree-Fock-Bogoliubov equations. The gap solitons are composed of a coherent condensate, and normal and anomalous densities of incoherent vapor cotrapped with the condensate. Both intragap and intergap solitons are constructed, with chemical potentials of the components falling in one or different band gaps in the OL-induced spectrum. Solitons change gradually with temperature. Families of intragap solitons are completely stable (both in direct simulations and in terms of eigenvalues of perturbation modes), while the intergap family may have a very small unstable eigenvalue (nevertheless, they feature no instability in direct simulations). Stable higher-order (multihumped) solitons and bound complexes of fundamental solitons are found too.

• OSTI ID: 20857742
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 3 Vol. 74; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
BOSE-EINSTEIN CONDENSATION
BOSE-EINSTEIN GAS
COMPLEXES
COMPUTERIZED SIMULATION
DENSITY
DISTURBANCES
EIGENFUNCTIONS
EIGENVALUES
HARTREE-FOCK METHOD
HARTREE-FOCK-BOGOLYUBOV THEORY
INSTABILITY
POTENTIALS
SOLITONS
TRAPPING
VAPORS