Topological quantum critical points in the extended Bose-Hubbard model

TL;DR

This paper uncovers topological quantum critical points in the 1D extended Bose-Hubbard model, revealing localized edge states and long-range order, and proposes an experimental scheme using quantum gas microscopy for dipolar atoms.

Contribution

It identifies and characterizes topological quantum critical points in a strongly-correlated model, linking topological phases with quantum criticality and edge states.

Findings

Two distinct topological quantum critical points with localized edge states.

Long-range ordered string correlation persists at critical points.

Proposed quantum gas microscopy scheme for experimental observation.

Abstract

The combination of topology and quantum criticality can give rise to an exotic mix of counterintuitive effects. Here, we show that unexpected topological properties take place in a paradigmatic strongly-correlated Hamiltonian: the 1D extended Bose-Hubbard model. In particular, we reveal the presence of two distinct topological quantum critical points with localized edge states and gapless bulk excitations. Our results show that the topological critical points separate two phases, one topologically protected and the other topologically trivial, both characterized by a long-range ordered string correlation function. The long-range order persists also at the topological critical points and it reflects the presence of localized edge states protected by a finite charge gap. Finally, we introduce a super-resolution quantum gas microscopy scheme for dipolar dysprosium atoms, which provides a reliable route towards the experimental study of topological quantum critical points.