Quantum adaptation of noisy channels

TL;DR

This paper introduces a quantum filtering method to adaptively manage noisy quantum channels, preventing entanglement sudden death and enhancing quantum communication robustness.

Contribution

It proposes a novel quantum filtering technique that prepares entangled states for subsequent channels, avoiding entanglement loss without distillation.

Findings

Probabilistic elimination of entanglement sudden death.

Application to quantum key distribution over noisy channels.

Effective management of isotropic noise in amplitude damping channels.

Abstract

Probabilistic quantum filtering is proposed to properly adapt sequential independent quantum channels in order to stop sudden death of entanglement. In the adaptation, the quantum filtering does not distill or purify more entanglement, it rather properly prepares entangled state to the subsequent quantum channel. For example, the quantum adaptation probabilistically eliminates the sudden death of entanglement of two-qubit entangled state with isotropic noise injected into separate amplitude damping channels. The result has a direct application in quantum key distribution through noisy channels.