Topological Edge-State Manifestation of Interacting 2D Condensed Boson-Lattice Systems in a Harmonic Trap

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.

8 pages (expanded Supplemental Material)

References in corpus (9)

• Topological Photonics
• Emergence of coherence in a uniform quasi-two-dimensional Bose gas
• Homogeneous Atomic Fermi Gases
• Real-space imaging of a topological protected edge state with ultracold atoms in an amplitude-chirped optical lattice
• Effects of Smooth Boundaries on Topological Edge Modes in Optical Lattices
• Spontaneous breaking of spatial and spin symmetry in spinor condensates
• Topological instabilities in ac-driven bosonic systems
• Occupation probabilities and current densities of bulk and edge states of a Floquet topological insulator
• Creating topological interfaces and detecting chiral edge modes in a 2D optical lattice

Cited by in corpus (9)

• Vector Topological Edge Solitons in Floquet Insulators
• Topological magnon amplification
• Interacting Hofstadter Interface
• Generalized Berry phase for a bosonic Bogoliubov system with exceptional points
• Strain and pseudo-magnetic fields in optical lattices from density-assisted tunneling
• Floquet Edge Multicolor Solitons
• Local Chern marker of smoothly confined Hofstadter fermions
• Topological gap solitons in Rabi Su-Schrieffer-Heeger lattices
• Many-body effects in the excitations and dynamics of trapped Bose-Einstein condensates