Hardcore bosonic domain walls on honeycomb lattice

TL;DR

This paper investigates bosonic domain walls on a honeycomb lattice, revealing topological charge-density-wave regions and superfluid transport along domain walls, with implications for cold atom experiments.

Contribution

It provides the first detailed quantum Monte Carlo study of topological bosonic domain walls on honeycomb lattices, highlighting their superfluid and insulator phases and topological properties.

Findings

Domain walls separate charge-density-wave regions with opposite Berry curvatures.

Superfluid transport occurs along the domain walls due to topological changes.

Zigzag domain walls exhibit higher superfluid density than armchair ones.

Abstract

Linelike hardcore bosonic domain walls in a staggered potential on honeycomb lattice are studied using quantum Monte Carlo simulations. The phase diagrams of ribbons with zigzag and armchair domain walls are mapped, which contain superfluid and insulator phases at various fillings. In the $\rho=\frac{1}{2}$ insulator, the domain wall separates two charge-density-wave (CDW) regions with opposite Berry curvatures. Associated with the change of topological properties, superfluid transport occurs down the domain wall. The superfluid density associated with a zigzag domain wall is much larger than that of an armchair domain wall due to the different arrangements of occupied and unoccupied sites along the domain wall. Our results provide a concrete context to study bosonic topological phenomena, which may be simulated experimentally using bosonic cold atoms trapped in optical lattices.