Stable knots in the trapped Bose-Einstein condensates
1 Department of Physics, Beijing Normal University - Beijing 100875, China
2 State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences Beijing 100190, China
Received: 1 April 2014
Accepted: 15 May 2014
The knot of the spin-texture is studied within the two-component Bose-Einstein condensates which are described by the nonlinear Gross-Pitaevskii equations. We start from the noninteracting equations including an axisymmetric harmonic trap to obtain an exact solution, which exhibits a nontrivial topological structure. The spin-texture is a knot with an integral Hopf invariant. The stability of the knot is verified by numerically evolving the nonlinear Gross-Pitaevskii equations along imaginary time.
PACS: 03.75.Mn – Multicomponent condensates; spinor condensates / 03.75.Lm – Tunneling, Josephson effect, Bose-Einstein condensates in periodic potentials, solitons, vortices, and topological excitations / 67.85.Fg – Multicomponent condensates; spinor condensates
© EPLA, 2014