Towards the chemical tuning of entanglement in molecular nanomagnets

TL;DR

This paper demonstrates how chemical substitutions in molecular nanomagnets can be used to tune and modulate quantum entanglement between spins, with implications for quantum information applications.

Contribution

It introduces a theoretical framework showing how magnetic defects affect entanglement distribution in antiferromagnetic spin rings, revealing new ways to control quantum correlations.

Findings

Magnetic defects cause spatial modulation of entanglement within spin rings.

Entanglement between local spins and collective ring states coexist in exchange-coupled dimers.

Features persist at finite temperatures and relate to observable quantities.

Abstract

Antiferromagnetic spin rings represent prototypical realizations of highly correlated, low-dimensional systems. Here we theoretically show how the introduction of magnetic defects by controlled chemical substitutions results in a strong spatial modulation of spin-pair entanglement within each ring. Entanglement between local degrees of freedom (individual spins) and collective ones (total ring spins) are shown to coexist in exchange-coupled ring dimers, as can be deduced from general symmetry arguments. We verify the persistence of these features at finite temperatures, and discuss them in terms of experimentally accessible observables.