skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Sign of coupling in barrier-separated Bose-Einstein condensates and stability of double-ring systems

Journal Article · · Physical Review. A
; ;  [1]
  1. Centre for Theoretical Chemistry and Physics and Institute of Natural Sciences, Massey University (Albany Campus), Private Bag 102 904, North Shore MSC, Auckland 0745 (New Zealand)

We revisit recent claims about the instability of nonrotating tunnel coupled annular Bose-Einstein condensates leading to the emergence of angular momentum Josephson oscillation [Phys. Rev. Lett. 98, 050401 (2007)]. It was predicted that all stationary states with uniform density become unstable in certain parameter regimes. By careful analysis, we arrive at a different conclusion. We show that there is a stable nonrotating and uniform ground state for any value of the tunnel coupling and repulsive interactions. The instability of an excited state with {pi} phase difference between the condensates can be interpreted in terms of the familiar snake instability. We further discuss the sign of the tunnel coupling through a separating barrier, which carries significance for the nature of the stationary states. It is found to always be negative for physical reasons.

OSTI ID:
21408341
Journal Information:
Physical Review. A, Vol. 81, Issue 2; Other Information: DOI: 10.1103/PhysRevA.81.025602; (c) 2010 The American Physical Society; ISSN 1050-2947
Country of Publication:
United States
Language:
English