Exponentially enhanced quantum communication rate by multiplexing continuous-variable teleportation

TL;DR

This paper demonstrates that multiplexing in continuous-variable quantum teleportation significantly boosts communication rates and loss resilience, offering a promising approach to overcoming energy and distance limitations in quantum communication.

Contribution

It introduces a multiplexed encoding scheme for continuous-variable teleportation, showing exponential rate improvements and analyzing optimal mode numbers for enhanced quantum communication.

Findings

Multiplexing exponentially increases quantum communication rates.

Multiplexing improves loss resilience in quantum channels.

Optimal mode number depends on entanglement thresholds.

Abstract

A major challenge of today's quantum communication systems lies in the transmission of quantum information with high rates over long distances in the presence of unavoidable losses. Thereby the achievable quantum communication rate is fundamentally limited by the amount of energy that can be transmitted per use of the channel. It is hence vital to develop quantum communication protocols that encode quantum information as energy efficiently as possible. To this aim we investigate continuous-variable quantum teleportation as a method of distributing quantum information. We explore the possibility to encode information on multiple optical modes and derive upper and lower bounds on the achievable quantum channel capacities. This analysis enables us to benchmark single-mode versus multi-mode entanglement resources. Our research reveals that multiplexing does not only feature an enhanced energy efficiency, leading to an exponential increase in the achievable quantum communication rates in comparison to single-mode coding, but also yields an improved loss resilience. However, as reliable quantum information transfer is only achieved for entanglement values above a certain threshold, a careful optimization of the number of coding modes is needed to obtain the optimal quantum channel capacity.