Eur. Phys. J. B 68, 317-328 (2009)
https://doi.org/10.1140/epjb/e2008-00407-3

Internal structure of a quantum soliton and classical excitations due to trap opening

Laboratoire Kastler Brossel, École Normale Supérieure, UPMC and CNRS, 24 rue Lhomond, 75231 Paris Cedex 05, France

Corresponding author: ^a yvan.castin@lkb.ens.fr

Received: 14 July 2008
Revised: 19 September 2008
Published online: 30 October 2008

Abstract

We analytically solve two problems that may be useful in the context of the recent observation of matter wave bright solitons in a one-dimensional attractive atomic Bose gas. The first problem is strictly beyond mean field: from the Bethe ansatz solution we extract the internal correlation function of the particle positions in the quantum soliton, that is for a fixed center of mass position. The second problem is solved in the limit of a large number of particles, where the mean field theory is asymptotically correct: it deals with the number of excitations created by the opening of the trap, starting from a pure soliton in a weakly curved harmonic potential.