Optimal quantum repeaters with doubly entangled state purification

TL;DR

This paper proposes an improved quantum repeater scheme utilizing doubly entangled photon pairs to enhance long-distance quantum communication efficiency despite noise and imperfect operations.

Contribution

It introduces a modified quantum repeater protocol that overcomes previous limitations by using doubly entangled states and accounts for realistic noise and operational imperfections.

Findings

Enhanced efficiency of quantum channels with doubly entangled photons

Overcoming noise limitations in quantum communication

Improved quantum repeater design for long-distance links

Abstract

Recently, Briegel et al. present a quantum repeaters protocol using nest entanglement purification for long distance quantum communication(Physical Review Letters \textbf{81},5932). In this paper we present a modified scheme for constructing an optimal quantum repeater using doubly entangled photon pairs that overcomes the limitations of quantum communication via noisy channels. Based on the imperfect quantum operations and classical communications, the polarization entangled quantum channels can be built with a better efficiency.