Bose-Hubbard realization of fracton defects

TL;DR

This paper demonstrates that an extended Bose-Hubbard model with ring-exchange interactions hosts fractonic defects, which are immobile excitations, and discusses their potential experimental realization in quantum simulators.

Contribution

It introduces a Bose-Hubbard-based model that realizes fractonic defects and analyzes their properties and robustness, advancing the understanding of fracton physics in bosonic systems.

Findings

Identifies fractonic defect excitations in the model

Shows defect mobility constraints through simulations

Proposes experimental platforms for realization

Abstract

Bose-Hubbard models are simple paradigmatic lattice models used to study dynamics and phases of quantum bosonic matter. We combine the extended Bose-Hubbard model in the hard-core regime with ring-exchange hoppings. By investigating the symmetries and low-energy properties of the Hamiltonian we argue that the model hosts fractonic defect excitations. We back up our claims with exact numerical simulations of defect dynamics exhibiting mobility constraints. Moreover, we confirm the robustness of our results against fracton symmetry breaking perturbations. Finally we argue that this model can be experimentally realized in recently proposed quantum simulator platforms with big time crystals, thus paving a way for the controlled study of many-body dynamics with mobility constraints.