Entanglement of spin-1/2 Heisenberg Antiferromagnetic quantum spin chains

TL;DR

This paper measures quantum entanglement in an infinite spin-1/2 Heisenberg antiferromagnetic chain at finite temperature, relating it to magnetic susceptibility and identifying a decoherence temperature that depends on exchange coupling.

Contribution

It introduces a novel entanglement measure based on the Hilbert-Schmidt norm and relates it to magnetic susceptibility in an infinite spin chain at finite temperature.

Findings

Entanglement is quantified for the first time in this system.

Decoherence temperature is identified and related to exchange coupling.

Exchange coupling may protect entanglement against thermal decoherence.

Abstract

The quantum entanglement measure is determined, for the first time, for a collection of spin-1/2 arranged in a infinite chain with finite temperature and applied to a single-crystal \beta-\mathrm{T_eVO_4}. The physical quantity proposed here to measure the entanglement is the distance between states by adopting the Hilbert-Schmidt norm. We relate the distance between states with the magnetic susceptibility. The decoherence temperature, above which the entanglement is suppressed, is determined for a system. A correlation among their decoherence temperatures and their respective exchange coupling constants is established, moreover, it is conjectured that the exchange coupling protects the system from decoherence as temperature increases.