Entanglement Transfer Through an Antiferromagnetic Spin Chain

TL;DR

This paper demonstrates that antiferromagnetic spin chains can effectively transmit entanglement faster, with less decay and higher purity, compared to ferromagnetic chains, even under non-zero temperature and environmental noise.

Contribution

It introduces the use of antiferromagnetic Heisenberg chains as efficient entanglement channels, highlighting their advantages over ferromagnetic chains in quantum communication.

Findings

Faster entanglement transmission with less decay in antiferromagnetic chains.

Higher purity and non-analytical pulse shape of transmitted entanglement.

Reduced environmental and thermal effects compared to ferromagnetic chains.

Abstract

We study the possibility of using an uniformly coupled finite antiferromagnetic spin-1/2 Heisenberg chain as a channel for transmitting entanglement. One member of a pair of maximally entangled spins is initially appended to one end of a chain in its ground state and the dynamical propagation of this entanglement to the other end is calculated. We show that compared to the analogous scheme with a ferromagnetic chain in its ground state, here the entanglement is transmitted faster, with less decay, with a much higher purity and as a narrow pulse form rising non-analytically from zero. Here non-zero temperatures and depolarizing environments are both found to be less destructive in comparison to the ferromagnetic case. The entanglement is found to propagate through the chain in a peculiar fashion whereby it hops to skip alternate sites.