Quench-produced solitons in a box-trapped Bose-Einstein condensate

Abstract

We describe a protocol to prepare solitons in a quasi-one-dimensional (quasi-1D) box-trapped Bose-Einstein condensate using a quench of the isotropic s-wave scattering length. A quench to exactly four times the initial 1D coupling strength creates one soliton at each boundary of the box, which then propagate in a uniform background density and collide with one another. In the ideal case, no nonsolitonic excitations are created during the quench. The procedure is robust against realistic box shapes, imperfections in the scattering length ramp rate, and a mismatch of the final scattering length. We simulate the condensate in full 3D and propose a modification to the protocol that is effective outside of the strict quasi-1D regime.