Spin chain model for correlated quantum channels

TL;DR

This paper investigates how correlations in a quantum spin chain environment affect quantum information transmission quality, revealing critical environmental effects on fidelity and purity.

Contribution

It introduces a model linking correlated quantum channels to a spin chain environment, analyzing the impact of environmental criticality on transmission fidelity and purity.

Findings

Correlations in the environment influence transmission fidelity and purity.

Environmental criticality causes notable changes in channel performance.

Bounds for the channel entropy are derived.

Abstract

We analyze the quality of the quantum information transmission along a correlated quantum channel by studying the average fidelity between input and output states and the average output purity, giving bounds for the entropy of the channel. Noise correlations in the channel are modeled by the coupling of each channel use with an element of a one dimensional interacting quantum spin chain. Criticality of the environment chain is seen to emerge in the changes of the fidelity and of the purity.