Temporally multiplexed quantum repeaters with atomic gases

TL;DR

This paper proposes a temporally multiplexed quantum repeater protocol using atomic gases, which could significantly improve quantum communication efficiency when combined with a resonant cavity to mitigate noise issues.

Contribution

The paper introduces a novel temporally multiplexed quantum repeater scheme with atomic gases, addressing noise challenges with a resonant cavity to enhance performance.

Findings

Multiplexing advantage is initially negated by noise from unobserved Stokes photon directions.

A moderate-finesse cavity can suppress noise and restore multiplexing benefits.

The proposed scheme promises substantial improvements in quantum repeater efficiency.

Abstract

We propose a temporally multiplexed version of the Duan-Lukin-Cirac-Zoller (DLCZ) quantum repeater protocol using controlled inhomogeneous spin broadening in atomic gases. A first analysis suggests that the advantage of multiplexing is negated by noise due to spin wave excitations corresponding to unobserved directions of Stokes photon emission. However, this problem can be overcome with the help of a moderate-finesse cavity which is in resonance with Stokes photons, but invisible to the anti-Stokes photons. Our proposal promises greatly enhanced quantum repeater performance with atomic gases.