Edge excitations of bosonic fractional quantum Hall phases in optical lattices

TL;DR

This paper investigates the edge excitations of bosonic fractional quantum Hall states in optical lattices, revealing their sensitivity to system parameters and confirming theoretical predictions for certain filling factors.

Contribution

It provides the first detailed analysis of edge spectra in bosonic lattice fractional quantum Hall phases, highlighting conditions for clear experimental signatures.

Findings

Edge excitations are sensitive to interedge hybridization and edge-bulk mixing.

Proper potentials and fluxes yield clear edge spectra even in small systems.

Edge spectra for ν=1/2 and ν=2/3 match chiral Luttinger liquid theory predictions.

Abstract

The rapid development of artificial gauge fields in ultracold gases suggests that atomic realization of fractional quantum Hall physics will become experimentally practical in the near future. While it is known that bosons on lattices can support quantum Hall states, the universal edge excitations that provide the most likely experimental probe of the topological order have not been obtained. We find that the edge excitations of an interacting boson lattice model are surprisingly sensitive to interedge hybridization and edge-bulk mixing for some confining potentals. With properly chosen potentials and fluxes, the edge spectrum is surprisingly clear even for small systems with strong lattice effects such as bandwidth. Various fractional quantum Hall phases for bosons can be obtained, and the phases \nu=1/2 and \nu=2/3 have the edge spectra predicted by the chiral Luttinger liquid theory.