Remote Quantum Networks based on Quantum Memories

TL;DR

This paper reviews recent progress and challenges in developing large-scale quantum networks using quantum memories and repeaters to overcome optical fiber losses for long-distance quantum communication.

Contribution

It provides a concise overview of current advancements, challenges, and future directions in remote quantum networks based on quantum memories.

Findings

Quantum repeaters enable long-distance entanglement distribution.

Significant progress has been made with atomic quantum memories.

Challenges include improving memory coherence and network scalability.

Abstract

Quantum networks, capable of transmitting arbitrary quantum states, provide a foundation for a wide range of quantum applications, including distributed quantum computing, distributed quantum sensing, and quantum communication. Photons are the natural carrier of information in quantum networks, but the exponential loss of optical fiber channels prevents the construction of large-scale quantum networks. A potential solution is implementing quantum repeaters based on quantum memories, which can efficiently establish long-distance entanglement from short-distance entanglement. In the past decades, intense efforts have been devoted to constructing large-scale quantum networks based on various atomic quantum memories. In this Perspective, we present a concise overview of current advancements in remote quantum networks, elucidate the imminent challenges that must be addressed, and discuss the future directions.