# Avoiding disentanglement of multipartite entangled optical beams with a correlated noisy channel

## TL;DR

This paper experimentally demonstrates how tripartite entangled optical beams can be protected and revived in noisy quantum channels using correlated noise, aiding the development of robust quantum networks.

## Contribution

It shows that entanglement can be preserved and revived in noisy channels through correlated noise, advancing quantum network reliability.

## Key findings

- Symmetric tripartite entangled beams are robust in pure lossy channels.
- Correlated noisy channels can revive entanglement destroyed by excess noise.
- Experimental validation of entanglement revival techniques in non-Markovian environments.

## Abstract

A quantum communication network can be constructed by distributing a multipartite entangled state to space-separated nodes. Entangled optical beams with highest flying speed and measurable brightness can be used as carriers to convey information in quantum communication networks. Losses and noises existing in real communication channels will reduce or even totally destroy entanglement. The phenomenon of disentanglement will result in the complete failure of quantum communication. Here, we present the experimental demonstrations on the disentanglement and the entanglement revival of tripartite entangled optical beams used in a quantum network. We discover that symmetric tripartite entangled optical beams are robust in pure lossy but noiseless channels. While in a noisy channel the excess noise will lead to the disentanglement and the destroyed entanglement can be revived by the use of a correlated noisy channel (non-Markovian environment). The presented results provide useful technical references for establishing quantum networks.