Bosonic Integer Quantum Hall effect in an interacting lattice model

TL;DR

This paper demonstrates the existence of a bosonic integer quantum Hall phase in an interacting lattice model, providing numerical evidence for its topological properties and edge states, and suggesting potential for experimental realization.

Contribution

It introduces a simple lattice model that stabilizes a bosonic SPT phase with quantized Hall conductance and gapless edge modes, advancing understanding of topological phases in lattice systems.

Findings

Quantized Hall conductance of |σ_xy|=2

Presence of two counter propagating gapless edge modes

Establishment of a bosonic integer quantum Hall phase in a lattice model

Abstract

We study a bosonic model with correlated hopping on a honeycomb lattice, and show that its ground state is a bosonic integer quantum Hall (BIQH) phase, a prominent example of a symmetry protected topological (SPT) phase. By using the infinite density matrix renormalization group method, we establish the existence of the BIQH phase by providing clear numerical evidence: (i) a quantized Hall conductance with $|\sigma_{xy}|= 2$ (ii) two counter propagating gapless edge modes. Our simple model is an example of a novel class of systems that can stabilize SPT phases protected by a continuous symmetry on lattices and opens up new possibilities for the experimental realization of these exotic phases.