Entanglement filter with Rydberg atoms

TL;DR

This paper introduces a Rydberg-atom-based entanglement filter that can deterministically select desired photonic entangled states with high fidelity, enabling scalable quantum information processing.

Contribution

It presents a novel entanglement filter using Rydberg atoms that preserves specific photonic entanglement and operates robustly in different regimes.

Findings

Achieves near-unity fidelity in entanglement filtering.

Operates effectively in both Rydberg blockade and dissipation regimes.

Enables scalable photonic quantum information processing.

Abstract

Devices capable of deterministically manipulating the photonic entanglement are of paramount importance, since photons are the ideal messengers for quantum information. Here, we report a Rydberg-atom-based entanglement filter that preserves the desired photonic entangled state and deterministically blocks the transmission of the unwanted ones. Photonic entanglement with near-unity fidelity can be extracted from an input state with an arbitrarily low initial fidelity. The protocol is inherently robust, and succeeds both in the Rydberg blockade regime and in the interaction-induced dissipation regime. Such an entanglement filter opens new routes toward scalable photonic quantum information processing with multiple ensembles of Rydberg atoms.