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arXiv · 0706.4176

Entanglement Transfer Through an Antiferromagnetic Spin Chain

Abolfazl Bayat·Sugato Bose
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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.

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Abolfazl Bayat, Sugato Bose. 2010-02-01. Entanglement Transfer Through an Antiferromagnetic Spin Chain. https://arxiv.org/abs/0706.4176

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