Observation of Hopping and Blockade of Bosons in a Trapped Ion Spin Chain

TL;DR

This paper demonstrates the control and observation of bosonic hopping and blockade phenomena in a trapped ion system, enabling the simulation of Hubbard models with tunable interactions at the single-site level.

Contribution

It introduces a novel experimental method to realize and control bosonic Hubbard systems using trapped ions with site-specific phonon blockades.

Findings

Observed free hopping of bosons between ion sites.

Implemented phonon blockades via Jaynes-Cummings coupling.

Showed tunable suppression of phonon hopping.

Abstract

The local phonon modes in a Coulomb crystal of trapped ions can represent a Hubbard system of coupled bosons. We selectively prepare single excitations at each site and observe free hopping of a boson between sites, mediated by the long-range Coulomb interaction between ions. We then implement phonon blockades on targeted sites by driving a Jaynes-Cummings interaction on individually addressed ions to couple their internal spin to the local phonon mode. The resulting dressed states have energy splittings that can be tuned to suppress phonon hopping into the site. This new experimental approach opens up the possibility of realizing large-scale Hubbard systems from the bottom up with tunable interactions at the single-site level.