Finite-size effects in the dynamics of few bosons in a ring potential

We study the temporal evolution of a small number N of ultra-cold bosonic atoms confined in a ring potential. Assuming that initially the system is in a solitary-wave solution of the corresponding mean-field problem, we identify significant differences in the time evolution of the density distributi...

Full description

Saved in:
Bibliographic Details
Published in:Journal of physics. B, Atomic, molecular, and optical physics Atomic, molecular, and optical physics, 2018-01, Vol.51 (3), p.35504
Main Authors: Eriksson, G, Bengtsson, J, Karabulut, E Ö, Kavoulakis, G M, Reimann, S M
Format: Article
Language:English
Subjects:
Atom and Molecular Physics and Optics
Atom- och molekylfysik och optik
exact diagonalization
few-body systems
Fysik
Natural Sciences
Naturvetenskap
Physical Sciences
quantum rings
time evolution
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We study the temporal evolution of a small number N of ultra-cold bosonic atoms confined in a ring potential. Assuming that initially the system is in a solitary-wave solution of the corresponding mean-field problem, we identify significant differences in the time evolution of the density distribution of the atoms when it instead is evaluated with the many-body Schrödinger equation. Three characteristic timescales are derived: the first is the period of rotation of the wave around the ring, the second is associated with a 'decay' of the density variation, and the third is associated with periodic 'collapses' and 'revivals' of the density variations, with a factor of N separating each of them. The last two timescales tend to infinity in the appropriate limit of large N, in agreement with the mean-field approximation. These findings are based on the assumption of the initial state being a mean-field state. We confirm this behavior by comparison to the exact solutions for a few-body system stirred by an external potential. We find that the exact solutions of the driven system exhibit similar dynamical features.
ISSN:0953-4075
1361-6455
DOI:10.1088/1361-6455/aaa05c