High-fidelity state transfer through long-range correlated disordered quantum channels

TL;DR

This paper demonstrates that long-range correlated disorder in quantum channels can enable high-fidelity quantum-state transfer, even with significant disorder, advancing robust quantum communication device design.

Contribution

It reveals that strong long-range correlations in disordered quantum channels facilitate near-perfect state transfer despite disorder, and shows mirror symmetry is less critical.

Findings

High-fidelity transfer in disordered channels with strong correlations

Disorder correlations improve robustness of quantum communication

Mirror symmetry has limited impact on transfer quality

Abstract

We study quantum-state transfer in $XX$ spin-$1/2$ chains where both communicating spins are weakly coupled to a channel featuring disordered on-site magnetic fields. Fluctuations are modelled by long-range correlated sequences with self-similar profile obeying a power-law spectrum. We show that the channel is able to perform an almost perfect quantum-state transfer in most of the samples even in the presence of significant amounts of disorder provided the degree of those correlations is strong enough. In that case, we also show that the lack of mirror symmetry does not affect much the likelihood of having high-quality outcomes. Our results advance a further step in designing robust devices for quantum communication protocols.