Topological edge state manifestation of interacting 2D boson lattices in a harmonic trap
Author(s)
Galilo, B
Lee, DKK
Barnett, R
Type
Journal Article
Abstract
In this Letter, it is shown that interactions can facilitate the emergence of topological edge states of quantum-degenerate bosonic systems in the presence of a harmonic potential. This effect is demonstrated with the concrete model of a hexagonal lattice populated by spin-one bosons under a synthetic gauge field. In fermionic or noninteracting systems, the presence of a harmonic trap can obscure the observation of edge states. For our system with weakly interacting bosons in the Thomas-Fermi regime, we can clearly see a topological band structure with a band gap traversed by edge states. We also find that the number of edge states crossing the gap is increased in the presence of a harmonic trap, and the edge modes experience an energy shift while traversing the first Brillouin zone which is related to the topological properties of the system. We find an analytical expression for the edge-state energies and our comparison with numerical computation shows excellent agreement.
Date Issued
2017-11-17
Date Acceptance
2017-10-25
Citation
Physical Review Letters, 2017, 119 (20)
ISSN
0031-9007
Publisher
American Physical Society
Journal / Book Title
Physical Review Letters
Volume
119
Issue
20
Copyright Statement
© 2017 American Physical Society
Identifier
http://arxiv.org/abs/1704.06285v1
Subjects
cond-mat.quant-gas
cond-mat.quant-gas
Notes
6 pages (expanded Supplemental Material)
Publication Status
Published
Article Number
203204
Date Publish Online
2017-11-17