Quantum Repeaters based on Deterministic Storage of a Single Photon in distant Atomic Ensembles

TL;DR

This paper proposes a quantum repeater protocol using deterministic single-photon storage in distant atomic ensembles, significantly improving entanglement distribution rates over long distances.

Contribution

It introduces a novel quantum repeater scheme that overcomes probabilistic limitations, enabling scalable long-distance entanglement with higher efficiency and robustness.

Findings

Achieves higher entanglement distribution rates than previous protocols

Robust against phase fluctuations in the quantum channel

Maintains high fidelity with negligible imperfections

Abstract

Quantum repeaters hold the promise to prevent the photon losses in communication channels. Most recently, the serious efforts have been applied to achieve scalable distribution of entanglement over long distances. However, the probabilistic nature of entanglement generation and realistic quantum memory storage times make the implementation of quantum repeaters an outstanding experimental challenge. We propose a quantum repeater protocol based on the deterministic storage of a single photon in atomic ensembles confined in distant high-finesse cavities and show that this system is capable of distributing the entanglement over long distances with a much higher rate as compared to previous protocols, thereby alleviating the limitations on the quantum memory lifetime by several orders of magnitude. Our scheme is robust with respect to phase fluctuations in the quantum channel, while the fidelity imperfection is fixed and negligibly small at each step of entanglement swapping.