Spatially Resolved Detection of a Spin-Entanglement Wave in a Bose-Hubbard Chain

TL;DR

This study demonstrates the local detection of spin entanglement waves in a Bose-Hubbard chain, revealing how entanglement propagates and diminishes with particle-number fluctuations, advancing understanding of quantum many-body systems.

Contribution

It introduces a method to measure local spin entanglement in a Bose-Hubbard chain, highlighting the dynamics of entanglement propagation and its dependence on particle fluctuations.

Findings

Detected an outward propagating spin entanglement wave.

Quantified the decrease of spin entanglement with particle-number fluctuations.

Provided insights into entanglement dynamics in quantum many-body systems.

Abstract

Entanglement is an essential property of quantum many-body systems. However, its local detection is challenging and was so far limited to spin degrees of freedom in ion chains. Here we measure entanglement between the spins of atoms located on two lattice sites in a one-dimensional Bose-Hubbard chain which features both local spin- and particle-number fluctuations. Starting with an initially localized spin impurity, we observe an outwards propagating entanglement wave and show quantitatively how entanglement in the spin sector rapidly decreases with increasing particle-number fluctuations in the chain.