Three-body spin mixing in spin-1 Bose-Einstein condensates

Year: 2021

Authors: Mestrom P. M. A.; Li J-L; Colussi V. E.; Secker T.; Kokkelmans S. J. J. M. F.

Autors Affiliation: Eindhoven University of Technology, P. O. Box 513, 5600 MB Eindhoven, The Netherlands; INO-CNR BEC Center and Dipartimento di Fisica, Universita di Trento, 38123 Povo, Italy

Abstract: We study zero-energy collisions between three identical bosons with spin f = 1 interacting via pairwise potentials. We quantify the corresponding three-body scattering hypervolumes, which parametrize the effective three-body interaction strengths in a many-body description of spin-1 Bose-Einstein condensates. Our results demonstrate universal behavior of the scattering hypervolumes for strong s- and p-wave two-body interactions. At weak interactions, we find that the real parts of the scattering hypervolumes are predominantly determined by hard-hyperspherelike collisions, which we characterize by a simple formula. With this universal result, we estimate that spin mixing via three-body collisions starts to dominate over two-body spin mixing at a typical particle density of 10(17) cm(-3) for Na-23 and K-41 spinor condensates. This density can be reduced by tuning the two-body interactions to an s- or p-wave dimer resonance or to a point where two-body spin mixing effectively vanishes. Another possibility to observe the effects of three-body spin mixing involves the application of weak magnetic fields to cancel out the effective two-body interaction strength in the characteristic timescale describing the spin dynamic


Volume: 104 (2)      Pages from: 023321-1  to: 023321-15

More Information: We thank Denise Ahmed-Braun, Gijs Groeneveld, and Silvia Musolino for stimulating discussions. This research is financially supported by the Netherlands Organisation for Scientific Research (NWO) under Grant No. 680-47-623. V.E.C. acknowledges additional financial support from Provincia Autonoma di Trento and the Italian MIUR under the PRIN2017 project CEnTraL.
DOI: 10.1103/PhysRevA.104.023321